What is the Latin word for external?

The usual Latin words for “external” are extrāneus, extrārius, externus; also internus. The right choice depends on the sense; see the distinctions below.

English → Latin

“external” in Latin

extrāneusforeign; strange extrāriusoutward, external, extrinsic; unrelated (person); stray (canis extrarius)externusoutward, external; foreign, alien, exotic, strange internusinward, internal; domestic, civil, internal

The English word external itself goes back to Latin exter, through externus.

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

external

extraneus (opposed to to what is on or in the thing itself; e.g., propter aliquam extraneus causam, opposed to the thing, ipsa propter se; also “not belonging to us;” opposed to our relations, country, etc., Cic.): extrarius (external, opposed to to one’s self; e.g., utilitas aut in corpore posita est, aut in rebus extrariis, Quint.): externus (outward, locally; applied to either things or persons; opposed to intestinus, or [post-classical] internus); also quod est extra (e.g., illa, quae sunt extra; external goods, Cic.). Compare exterior, when spoken of two things (opposed to interior): the external portion, pars exterior: external ornaments, extranea ornamenta: external advantages, bona externa, bona corporis (of personal advantages): external heat, tepor externus: external applications, remedia, quae extrinsecus adhibentur (of remedies applied externally): external aid, adjumenta externa et adventiciar: to contemplate external objects, ea, quae extra sunt, contemplari (Cic.): the lungs draw in the external air, pulmones extrinsecus spiritum adducunt (Cic.): at the sight of some external object, objecta re (e.g., terribili) extrinsecus; not excited by any external force, neque (non) ulla vi extrinsecus excitatus.

Quick answer

What is the Latin word for external?: The usual Latin words for “external” are extrāneus, extrārius, externus; also internus. 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.