• WordNet 3.6
    • adj spectral resembling or characteristic of a phantom "a ghostly face at the window","a phantasmal presence in the room","spectral emanations","spiritual tappings at a seance"
    • adj spectral of or relating to a spectrum "spectral colors","spectral analysis"
    • ***
Webster's Revised Unabridged Dictionary
    • Spectral Of or pertaining to a specter; ghosty. "He that feels timid at the spectral form of evil is not the man to spread light."
    • Spectral (Opt) Of or pertaining to the spectrum; made by the spectrum; as, spectral colors; spectral analysis.
    • ***
Century Dictionary and Cyclopedia
    • spectral Of or pertaining to a specter; resembling or having the aspect of a specter; ghostlike: ghostly.
    • spectral Pertaining to ocular spectra, or pertaining to the solar, prismatic, or diffraction spectrum; exhibiting the hues of the prismatic spectrum; produced by the aid of the spectrum: as, spectral colors; spectral analysis.
    • spectral In zoology, like or likened to a specter or apparition; suggestive of a ghost in any way: as, the spectral bat; spectral shrimps; spectral insects.
    • ***
Chambers's Twentieth Century Dictionary
    • adj Spectral relating to, or like, a spectre
    • ***


  • Joseph Conrad
    “How does one kill fear, I wonder? How do you shoot a specter through the heart, slash off its spectral head, take it by its spectral throat?”
  • Karl Kraus
    “Science is spectral analysis. Art is light synthesis.”
  • John Berger
    “Modern thought has transferred the spectral character of Death to the notion of time itself. Time has become Death triumphant over all.”


Chambers's Twentieth Century Dictionary
L. spectrum, a vision—specĕre, to see.


In literature:

It was only when a little dog ran along the spectral path and suddenly vanished into thin air that I discovered the illusion.
"Real Ghost Stories" by William T. Stead
Outside the window, the dark scene of rocks and vehicles and men was fading; turning ghostly, shadowy, spectral.
"The White Invaders" by Raymond King Cummings
The people were white, spectral shapes, transparent!
"Wandl the Invader" by Raymond King Cummings
It made a strange picture in the moonlight, with its black-curved beak and its spectral crew.
"The Best Short Stories of 1917" by Various
The parallel harmony among the spectral colors is blue, violet, and orange.
"The Continental Monthly , Vol. 2 No. 5, November 1862" by Various
Like a spectral invitation, those five letters, F-a-n-n-y, gleamed before him so seductively.
"A Hungarian Nabob" by Maurus Jókai
Like as in the same spectral phenomenon, too, this vessel seemed to be gliding towards them without sound or apparent motion.
"Bob Strong's Holidays" by John Conroy Hutcheson
The story is, of course, one of which the violent contrasts and spectral catastrophe could only take place, or be conceived, in a large city.
"On the Old Road, Vol. 2 (of 2)" by John Ruskin
It is evanescent, spectral, now.
"The Bibliotaph" by Leon H. Vincent
They were gray, dim, spectral shapes and new to the region.
"Black Bruin" by Clarence Hawkes
Even their spectral life has gone out of them; they are rigid now, and only the strings set them dancing.
"Figures of Several Centuries" by Arthur Symons
Everything in the prison yard was dim and gray and spectral.
"Army Boys on the Firing Line" by Homer Randall
Soon the spectral object was seen to advance more distinctly out of the gloom.
"The Young Trawler" by R.M. Ballantyne
He, too, recognised us, for his bright spectral eyes opened wide when he saw us.
"The Gorilla Hunters" by R.M. Ballantyne
In a few minutes the tall and graceful column itself became visible, looking pale and spectral against the black sky.
"The Lighthouse" by R.M. Ballantyne
The figure of the Indian, with something dark upon its shoulder, emerged from the spectral forest, and came towards them through the mist.
"Prisoners of Hope" by Mary Johnston
For, after all, it is a tragedy, full of spectral terrors.
"The Atlantic Monthly, Volume 17, No. 103, May, 1866" by Various
The savages would fancy nine hundred under the mystifying shadows of that spectral-like grove.
"The War Trail" by Mayne Reid
On and on they sped up the dull gray road, a spectral rider on a spectral horse.
"Mistress Anne" by Temple Bailey
At night he heard it move, with a spectral rustling, under his pillow where he kept it.
"Sally of Missouri" by R. E. Young

In poetry:

A weird and spectral presence came
Between me and the light;
The waving of a shadowy hand
That faded into night.
"The Highland Girl's Lament" by Mary Gardiner Horsford
A spectral ocean lies outside,
Torn by a tempest dark;
Its ghostly billows, dim descried,
Leap on my stranded bark.
"Songs of the Winter Days" by George MacDonald
Now, in this afternoon
Enchanted, blue and brief,
The year has lost its grief
In valleys mute below the spectral moon.
"December" by Clark Ashton Smith
'Twere better far, O beautiful Rain,
That you swelled the torrent and flooded the main;
And that Winter, with all his spectral train,
Alone lay camped on the icy plain.
"The Rain: A Song Of Peace" by Denis Florence MacCarthy
God have mercy!—icy cold
Spectral hands her own enfold,
Drawing silently from them
Love's fair gifts of gold and gem.
"Waken! save me!" still as death
At her side he slumbereth.
"The New Wife and the Old" by John Greenleaf Whittier
Dimly out of the baffled sight
Houses and church-spires stretch away;
The trees, all spectral and still and white,
Stand up like ghosts in the failing light,
And fade and faint with the blinded day.
"Snow" by Elizabeth Akers Allen

In news:

The new detector is reportedly a thermoelectrically cooled 50 mm2 silicon drift detector (SDD) capable of high-resolution spectral acquisition at high count rates.
Wheatstone will introduce an all-new tabletop IP control surface , several IP audio products and an updated spectral audio processor at IBC2012.
No instrument with the spectral imager 's proposed capabilities currently exists.
Spectral Graph Transducer(SGT) is one of the superior graph-based transductive learning methods for classification.
INTERVIEWS Sample Eyes, Wings & Many Other Things' Spectral Drone-Rock on 'Cruelty'.
Sample Eyes, Wings & Many Other Things' Spectral Drone-Rock on 'Cruelty'.
University of Arizona at Work on New Terahertz Spectral Imager.
Spectral Graph Transducer(SGT) is one of the superior graph-based transductive learning methods for classification.
Spectral Graph Transducer (SGT) is one of the superior graph-based transductive learning methods for classification.
Applying structural and spectral integration to optical spectroscopy.
Capturing the Artistry of Spectral Interpretation.
The Eye-One iSis is designed to produce spectral measurements at a high speed for high-volume production environments.
Heiko Buelow, Andreas Birk, "Spectral 6DOF Registration of Noisy 3D Range Data with Partial Overlap," IEEE Transactions on Pattern Analysis and Machine Intelligence, vol 99, no.
This four-part article series draws to a close with a practical example of designing a multipart FIR filter to meet the spectral-mask requirements of GSM cellular systems.
CropSpec uses two sensors to measure spectral reflectance using light from pulsing laser diodes focused on the plants.

In science:

The only problem is that an integral of the pre-kernel over the complete spectrum contributes to the spectral density and the spectral correlators.
Spectral Universality of Real Chiral Random Matrix Ensembles
By the spectral theorem, we can write P = P+ + P0 + P− , where P± and P0 are selfadjoint operators corresponding to the spectral subspaces H+ , H− , and H0 = ker P for the sets (0, ∞), (−∞, 0), and {0}.
A note on interpolation in the generalized Schur class
Thus λ1 (G) is equal to the spectral norm or the spectral radius of A(G).
THe largest eigenvalue of sparse random graphs
Previous X-ray spectral analyses of M82 have shown that multiple spectral components are needed (for instance, Moran & Lehnert 1997; Ptak et al. 1997), indicating the presence of multi-phase X-ray emitting material.
First Look XMM-Newton EPIC Observations of the Prototypical Starburst Galaxy M82
With the weakening of the G-band, it is clear that the spectral type inferred from the blue spectral region is later in our data than in the data of BA92.
Evidence for high accretion-rates in Weak-Line T Tauri stars?
Therefore, the existence of the pro jection operator E (V ; T ) for each spectral set V does not imply a spectral pro jection-valued measure decomposition of T (see also ).
Line antiderivations over local fields and their applications
Spectral integration and spectral theory for non-Archimedean Banach spaces.
Line antiderivations over local fields and their applications
When the spectral density such as DOS and linear response function, the dimension N of matrix in the above estimation should be replaced by Nef f , the number of resonances with in the spectral resolution η , e.g.
Random phase vector for calculating the trace of a large matrix
Finally, we employ the relation (9) between the mean spectral density and the expectation value of the modulus of the spectral determinant for GOE matrices, and substitute the resulting expression into the integral (7).
Complexity of Random Energy Landscapes, Glass Transition and Absolute Value of Spectral Determinant of Random Matrices
We found that, for these afterglows, best fit spectral models are consistent with null extinction for both the two tested spectral indexes.
Absorption in Gamma Ray Burst afterglows
As one can see, the spectral parameter errors at the 90 % con fidence level are compatible with no spectral variation.
The XMM-Newton observation of GRB 040106 : evidence for an afterglow in a wind environment
Spectral types from other authors given in Tables 1 and 2 are often the result of comparison to RECONS spectral types.
The Solar Neighborhood X: New Nearby Stars in the Southern Sky and Accurate Photometric Distance Estimates for Red Dwarfs
Voiculescu [122] that the spectral measure of this sum converges toward the free convolution µA ⊞ µB if the spectral measure of A (resp. B ) converges toward µA (resp . µB ) as the size of the matrices goes to infinity.
Large deviations and stochastic calculus for large random matrices
It is easy to see that if the entries of the matrix are not Gaussian, the variations of the spectral measures will depend on much more general functions of the entries than those of the spectral measure.
Large deviations and stochastic calculus for large random matrices
Figure 10: Behaviour of the spectral density close to the spectral edge.
Introduction to the Random Matrix Theory: Gaussian Unitary Ensemble and Beyond