Etymology
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ides (n.)
"middle day of a Roman month," early 14c., from Old French ides (12c.), from Latin idus (plural) "the ides," a word perhaps of Etruscan origin. In the Roman calendar the eighth day after the nones, corresponding to the 15th of March, May, July, and October; the 13th of other months. "Debts and interest were often payable on the ides" [Lewis].
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Ido 
1908, artificial language devised in 1907 and based on Esperanto; from Ido -ido "offspring," suffix representing Latin -ida, Greek -ides.
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-idae 
word-forming element used to coin family names in zoology (by being suffixed to the name of the genus whence that of the family is derived), from Latin -idae, plural of noun suffix -ides (see -id).
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-id 
adjectival word-forming element, especially in zoology, "belonging to, connected with, member of a group or class," in some cases probably via from French -ide, back-formed from Modern Latin names of zoological classes in -idae, as arachnid "a spider" from the biological class name arachnidae.

This -idae is the plural of Latin -ides, a masculine patronymic (indicating "descent from"), from Greek -ides "son of," denoting descent from the person to whose name it is attached (such as Heraklides).

In astronomy, of meteor showers, "having its radiant in" the constellation named (Perseid, Leonid, etc.), it probably represents Latin -idis, from Greek -idos, the genitive of the feminine form of the patronymic suffix.
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nones (n.)

late 14c. in reference to the Roman calendar, "ninth day (by inclusive reckoning) before the ides of each month" (7th of March, May, July, October, 5th of other months), from Old French nones and directly from Latin nonæ (accusative nonas), fem. plural of nonus "ninth," contracted from *novenos, from novem "nine" (see nine).

The ecclesiastical sense of "daily office said originally at the ninth hour of the day" is from 1709; originally fixed at ninth hour from sunrise, hence about 3 p.m. (now usually somewhat earlier), from Latin nona (hora) "ninth (hour)," from fem. plural of nonus "ninth." It was also used from c. 1300 in a general sense of "midday" (see noon). For for the nones, see nonce.

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February (n.)

month following January, late 14c., ultimately from Latin februarius mensis "month of purification," from februare "to purify," from februa "purifications, expiatory rites" (plural of februum "means of purification, expiatory offerings"), which is of uncertain origin, said to be a Sabine word. De Vaan says from Proto-Italic *f(w)esro-, from a PIE word meaning "the smoking" or "the burning" (thus possibly connected with fume (n.)). The sense then could be either purification by smoke or a burnt offering.

The last month of the ancient (pre-450 B.C.E.) Roman calendar, so named in reference to the Roman feast of purification, held on the ides of the month. The Old English name for it was solmonað, which is said to mean "mud month." English first borrowed the Roman name from Old French Feverier, which yielded Middle English Feverer, Feoverel, etc. (c. 1200) before the 14c. respelling to conform to Latin.

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