a prefix used freely in English and meaning "not, lack of," or "sham," giving a negative sense to any word, 14c., from Anglo-French noun-, from Old French non-, from Latin non "not, by no means, not at all, not a," from Old Latin noenum "not one" (*ne oinom, from PIE root *ne- "not" + PIE root *oi-no- "one, unique"). In some cases perhaps from Middle English non "not" (adj.), from Old English nan (see not). "It differs from un- in that it denotes mere negation or absence of the thing or quality, while un- often denotes the opposite of the thing or quality" [Century Dictionary].
early 15c., "to copulate" (of wolves, dogs), literally "to range (things) in a line," from Old French alignier "set, lay in line" (Modern French aligner), from à "to" (see ad-) + lignier "to line," from Latin lineare "reduce to a straight line," from linea (see line (n.)). Transitive or reflexive sense of "to fall into line" is from 1853. International political sense is attested from 1934. The French spelling with -g- is unetymological, and aline was an early form in English. Related: Aligned; aligning.