What is the Latin word for observance?

The usual Latin words for “observance” are observō, observātiō, obtempĕrātĭo; also ūtor, mōs. The right choice depends on the sense; see the distinctions below.

English → Latin

“observance” in Latin

observōto observe, watch, pay attention to; to guard, keep watch over; to heed, regard, respect observātiōwatching, observing; observation, attention; surveillance obtempĕrātĭoa complying with ūtorto use, make use of, employ; to enjoy, indulge in, take advantage of; to experience, undergo, encounter mōsway or manner (of behaving); behavior; conduct; custom; habit; practice; usage; wont; character; disposition; inclinatio

The English word observance itself goes back to Latin observantia.

Riddle & Arnold A Copious and Critical English–Latin Lexicon, 1864

observance

Act of observing, regard, attention, observantia (outward respect or attention): observatio (reverence, regard): obedientia; obtemperatio (e.g., justitia est obtemperatio legibus, observance of the laws, Cic.).

Rule of practice, custom, usus mos receptus; consuetudo recepta: it is an observance, usu, more, con suetudine receptum est.

Quick answer

What is the Latin word for observance?: The usual Latin words for “observance” are observō, observātiō, obtempĕrātĭo; also ūtor, mōs. The right choice depends on the sense; see the distinctions below.

Entry from J. E. Riddle & T. K. Arnold, A Copious and Critical English–Latin Lexicon (rev. C. Anthon, New York: Harper, 1864), digitised by Fergus J. P. Walsh, CC BY-SA 4.0; Latin markup adapted by latindictionary.co.