equable (adj.)

1530s, from Latin aequabilitatem (nominative aequabilitas) "equality, uniformity, evenness," figuratively "impartiality," from aequabilis "equal, consistent, uniform" (see equable).

early 15c., "to make similar or the same; to balance or harmonize; distribute (ingredients) uniformly; reduce to evenness or smoothness; to set (a fracture)," from Latin aequatus "level, levelled, even, side-by-side," past participle of aequare "make even or uniform, make equal," from aequus "level, even, equal" (see equal (adj.)). Earliest use in English was of astrological calculation, then "to make equal;" meaning "to regard as equal" is early 19c. Related: Equated; equating.

"not uniform, changeable," 1716, from Latin inaequabilis "unequal," from in- "not" (see in- (1)) + aequabilis "similar, equal; constant, not varying" (see equable). Related: Inequability (1580s).