incurious adj.

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., "subtle, sophisticated;" late 14c., "eager to know, inquisitive, desirous of seeing" (often in a bad sense), also "wrought with or requiring care and art;" from Old French curios "solicitous, anxious, inquisitive; odd, strange" (Modern French curieux) and directly from Latin curiosus "careful, diligent; inquiring eagerly, meddlesome," akin to cura "care" (see cure (n.)).

The objective sense of "exciting curiosity" is by 1715 in English. In booksellers' catalogues, the word was a euphemism for "erotic, pornographic" (1877); such material was called curiosa (1883), the Latin neuter plural of curiosus. Related: Curiously; curiousness. Curiouser and curiouser is from "Alice's Adventures in Wonderland" (1865).

Curious and inquisitive may be used in a good or a bad sense, but inquisitive is more often, and prying is only, found in the latter. Curious expresses only the desire to know; inquisitive, the effort to find out by inquiry; prying, the effort to find out secrets by looking and working in improper ways. [Century Dictionary]