apodictic "clearly demonstrated," 1650s, from L. apodicticus, from Gk. apodeiktikos, from apodeiktos, verbal adjective of apodeiknynai "to show off, demonstrate," lit. "to point away from" (other objects, at one), from apo "off, away" (see apo-) + deiknynai "to show" (see diction).
1520s, from M.L. dictionarium "collection of words and phrases," from L. dictionarius "of words," from dictio "word" (see diction). Probably first English use in title of a book was in Sir Thomas Elyot's "Latin Dictionary" (1538) though L. Dictionarius was so used from early 13c.
1540s, "a word;" 1580s, "expression of ideas in words," from L.L. dictionem (nom. dictio) "a saying, expression, word," from dic-, pp. stem of L. dicere "speak, tell, say," related to dicare "proclaim, dedicate," from PIE base *deik- "to point out" (cf. Skt. dic- "point out, show," Gk. deiknynai "to prove," L. digitus "finger," O.H.G. zeigon, Ger. zeigen "to show," O.E. teon "to accuse," tæcan "to teach").
1660s, from L. dictum "thing said (a saying, bon-mot, prophecy, etc.), an order, command," neut. of dictus, pp. of dicere "say" (see diction). In legal use, a judge's expression of opinion which is not the formal resolution of a case.
late 14c., "numeral below 10," from L. digitus "finger or toe" (also with secondary meanings dealing in counting and numerals), related to dicere "tell, say, point out" (see diction). Numerical sense is because numerals under 10 were counted on fingers. The "finger or toe" sense in English is attested from 1640s.
1828, from Latinized form of Gk. deiktikos "able to show," from deiktos "shown," verbal adj. from deiknynai "to show" (see diction).