• WordNet 3.6
    • n rictus a gaping grimace
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Webster's Revised Unabridged Dictionary
    • n Rictus The gape of the mouth, as of birds; -- often resricted to the corners of the mouth.
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Century Dictionary and Cyclopedia
    • n rictus In ornithology, the gape of the bill; the cleft between the upper and the lower mandible when the mouth is open.
    • n rictus In botany, the throat, as of a calyx, corolla, etc.; the opening between the lips of a ringent or personate flower.
    • ***
Chambers's Twentieth Century Dictionary
    • n Rictus rikā€²tus the gape of the bill: the throat of the calyx
    • ***


Webster's Revised Unabridged Dictionary
L., the aperture of the mouth
Chambers's Twentieth Century Dictionary
L., a gaping.


In literature:

A rictus of cruel malignity lit up greyly their old bony faces.
"A Portrait of the Artist as a Young Man" by James Joyce
No one could escape from this rictus.
"The Man Who Laughs" by Victor Hugo
His gold tooth, gleaming in the light, made his rictus of passion more venomous, more malevolent still.
"The Air Trust" by George Allan England
The Vegan girl's mouth formed a rictus of pain.
"Equation of Doom" by Gerald Vance
He lay back on the pillows again, with a smile that was twisted into a rictus of agony as a twinge wrung the injured limb.
"The House 'Round the Corner" by Gordon Holmes
Rictus amplissimi infra oculos aperientes.
"Zoological Illustrations, Volume I" by William Swainson
Frons, rictus, et mentum vibrissis rigidis, elongatis, armati.
"Zoological Illustrations, Volume II" by William Swainson
Vargus grinned suddenly, a momentary rictus that came and went, utterly horrible.
"The Air Pirate" by Cyril Arthur Edward Ranger Gull

In news:

Have you ever been told to shut your rictus .