indetermination n.

word-forming element meaning "not, opposite of, without" (also im-, il-, ir- by assimilation of -n- with following consonant, a tendency which began in later Latin), from Latin in- "not," cognate with Greek an-, Old English un-, all from PIE root *ne- "not."

In Old French and Middle English often en-, but most of these forms have not survived in Modern English, and the few that do (enemy, for instance) no longer are felt as negative. The rule of thumb in English has been to use in- with obviously Latin elements, un- with native or nativized ones.

mid-14c., determinacioun, "decision, sentence in a suit at law, definite or authoritative judicial settlement," from Old French déterminacion "determination, settlement, definition" (14c.) and directly from Medieval Latin determinationem (nominative determinatio) "conclusion, boundary," noun of action from past-participle stem of Latin determinare "to enclose, bound, set limits to" (see determine).

Meaning "action of definitely ascertaining" is from 1670s; that of "result ascertained, a conclusion" is from 1560s. As "fixed direction toward a goal or terminal point," from 1650s, originally in physics or anatomy; metaphoric sense "fixation of will toward a goal, state of mental resolution with regard to something" is from 1680s; general sense of "quality of being resolute, fixedness of purpose as a character trait" is by 1822.