word-forming element meaning "four, having four, consisting of four," a variant of quadri- which was used in Latin especially before -p-, from an older form of the element which perhaps was influenced later by tri-.
word-forming element of Latin origin (in mischief, miscreant, misadventure, misnomer, etc.), from Old French mes- "bad, badly, wrong, wrongly," from Vulgar Latin *minus-, from Latin minus "less" (from suffixed form of PIE root *mei- (2) "small"), which was not used as a prefix in Latin but in the Romanic languages was affixed to words as a depreciative or negative element. The form in French perhaps was influenced in Old French by *miss-, the Frankish (Germanic) form of mis- (1).
word-forming element meaning "against, in opposition," from Latin adverb and preposition contra "against" (see contra (prep., adv.)). The Latin word was used as a prefix in Late Latin. In French, it became contre- and passed into English as counter-. The Old English equivalent was wiðer (surviving in withers and widdershins), from wið "with, against."
assimilated form of com- "with, together" before stems beginning in -l-. In early Latin, com- was assimilated to these as con-, but col- later also was used. Latin words in coll- became col- in Old French and thus in early Middle English but were altered back to coll- with the revival of learning.
word-forming element usually meaning "with, together," from Latin com, archaic form of classical Latin cum "together, together with, in combination," from PIE *kom- "beside, near, by, with" (compare Old English ge-, German ge-). The prefix in Latin sometimes was used as an intensive.
Before vowels and aspirates, it is reduced to co-; before -g-, it is assimilated to cog- or con-; before -l-, assimilated to col-; before -r-, assimilated to cor-; before -c-, -d-, -j-, -n-, -q-, -s-, -t-, and -v-, it is assimilated to con-, which was so frequent that it often was used as the normal form.
consonantal digraph, an initial sequence used in Latin (and thus in English words from Latin) to represent Greek initial aspirated r-. The medial Greek form of it usually is represented by -rrh-, as in catarrh, diarrhea, hemorrhage, myrrh, Pyrrhic. As it was pronounced as simply "r" in Middle English (as in Old French and Spanish), the -h- tended to be dropped in spelling but was restored in early Modern English with the classical revival.