What is the Latin word for voucher?

The usual Latin words for “voucher” are auctor, testis, cōnfirmō; also gravis. The right choice depends on the sense; see the distinctions below.

English → Latin

“voucher” in Latin

auctorseller, vendor; author, originator; sponsor, advocate testiswitness; one who testifies or attests cōnfirmōto make firm, establish, re-establish, strengthen, fortify, mature, confirm; to encourage, animate, embolden; persuade; gravisheavy; pregnant; troublesome, hard

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

voucher

One who vouches for anything, auctor (general term): testis (a witness; PROP. or figuratively): confirmator (only PROP.; one that gives security for money; Vid: Cic., Cluent., 26, 77). A sure voucher, auctor or testis locuples (PROP.); auctor certus or gravis (PROP. and figuratively).

Receipt produced. To produce vouchers of one’s account, *rationem apochis additis probare.

A warrant, Vid.

Quick answer

What is the Latin word for voucher?: The usual Latin words for “voucher” are auctor, testis, cōnfirmō; also gravis. 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.