• WordNet 3.6
    • n pentacle a star with 5 points; formed by 5 straight lines between the vertices of a pentagon and enclosing another pentagon
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Webster's Revised Unabridged Dictionary
    • n Pentacle A five-pointed star, also called a pentagram or pentalpha. See illustr. under pentalpha. Sometimes referring to a similar figure, such as the figure composed of two equilateral triangles intersecting so as to form a six-pointed star. It was used in early ornamental art, and also with superstitious import by the astrologers and mystics of the Middle Ages. The six-pointed star is more comonly called a hexagram, or called Solomon's seal; it resembles the star of David (Magen David
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Century Dictionary and Cyclopedia
    • n pentacle Corrupt forms of pantofle.
    • n pentacle A mathematical figure used in magical ceremonies, and considered a defense against demons. It was probably with this figure that the Pythagoreans began their letters, as a symbol of health. In modern English books it is generally assumed that this is the six-pointed star formed of two triangles interlaced or superposed. (Compare Solomon's seal, under seal.) Obviously, the pentacle must be a five-pointed or five-membered object, and it should be considered as equivalent to the pentagram or pentalpha. (See also pentangle.) The construction of the five-pointed star depends upon an abstruse proposition discovered in the Pythagorean school, and this star seems to have been from that time adopted as their seal.
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Chambers's Twentieth Century Dictionary
    • n Pentacle pent′a-kl a figure formed by two equilateral triangles intersecting regularly so as to form a six-pointed star: properly a five-pointed object, the same as Pentagram (q.v.), a defence against demons
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Webster's Revised Unabridged Dictionary
Gr. pe`nte five
Chambers's Twentieth Century Dictionary
O. Fr., but prob. not from Gr. pente, five, but O. Fr. pente, pendre, to hang. As applied to a magical figure prob. a corr. of pentangle, perh. pentacolpendre, to hang, a, on, col, the neck.


In literature:

I mounted the stairs; I looked on the floor of the upper room; yes, there still was the black figure of the pentacle, the circle.
"A Strange Story, Complete" by Edward Bulwer-Lytton
It was only a partial 'defense' therefore, and I nearly died in the pentacle.
"Carnacki, The Ghost Finder" by William Hope Hodgson
I knew that the pentacle would govern her, and the ring must bind, until I gave the word.
"The Haunters & The Haunted" by Various
When I first saw him he was tracing circles and pentacles in the grass and talking the language of the elves.
"Magic" by G.K. Chesterton
Do you meet with a pentacle?
"From a Cornish Window" by Arthur Thomas Quiller-Couch

In news:

"Incorruptible": Pentacle Theatre in Salem holds auditions Oct 27 for men and women, ages 20-70, for roles in the dark comedy.
In March of 2006, I reported that the widow of a Nevada National Guardsman shot down in Afghanistan was trying to get permission from the Department of Veterans Affairs to have a pentacle engraved on her husband's headstone.
For Sgt Patrick Stewart's family, the symbol of choice was also from his religion: the Wiccan pentacle .
The pentacle joins 38 religious symbols already allowed by the V.A.

In science:

While in the conventional metal or semiconductor with massive carriers, there is no pseudospin related berry phase, the inverse of peak height is ∝ n+ 1 2 (see dotted pentacle symbol in Fig.2(b)).
Nernst and Seebeck effect in a graphene nanoribbon