unguent n.

mid-14c., enointen, "pour oil upon, smear with ointment," from Old French enoint "smeared on," past participle of enoindre "smear on," from Latin inunguere "to anoint," from in- "in, into" (see in) + unguere "to smear" (see unguent (n.)).

Forms in a- by late 14c. Originally in reference to grease or oil smeared on for medicinal purposes; its use in the Coverdale Bible in reference to Christ (as in The Lord's Anointed; see chrism) has spiritualized the word. Related: Anointed; anointing (c. 1300 as a verbal noun).

"unctuous medicinal salve for external application," late 13c., oynement, from Old French oignement "ointment, salve, unguent," from Vulgar Latin *unguimentum, from Latin unguentum (see unguent). The first -t- emerged early 14c. in English, from Old French, which got it by influence of oint, past participle of the verb oindre "to anoint."