late 14c., "having the quality of continuing long in being," from Old French durable (11c.) and directly from Latin durabilis "lasting, permanent," from durare "to harden," from durus "hard," from PIE *dru-ro-, suffixed variant form of root *deru- "be firm, solid, steadfast." From late 13c. as a surname (probably meaning "steadfast"). Related: Durably. Durable goods attested from 1930.
1767, "a lowering of value" (originally of currency), noun of action from depreciate. Sense of "a belittling, deliberate underestimation of the merits of a person, action, or thing" is from 1790. Meaning "loss of value of a durable good by age or wear" is from 1900.
"in the matter of, in the (legal) case of," c. 1600, probably from Duns Scotus; Latin, from re, ablative of res "property, goods; matter, thing, affair," from Proto-Italic *re-, from PIE *reh-i- "wealth, goods" (source also of Sanskrit rayi- "property, goods," Avestan raii-i- "wealth").