PRISM n.
-- Nicol's prism, Nicol prism. Etym: [So called from Wm. Nicol, of Edinburgh, who first proposed it.] (Opt.) An instrument for experiments in polarization, consisting of a rhomb of Iceland spar, which has been bisected obliquely at a certain angle, and the two parts again joined with transparent cement, so that the o…
PRO- n.
fix signifying before, in front, forth, for, in behalf of, in place of, according to; as, propose, to place before; proceed, to go before or forward; project, to throw forward; prologue, part spoken before (the main piece); propel, prognathous; provide, to look out for; pronoun, a word instead of a noun; proconsul, a p…