O / offensācŭlum
noun

offensācŭlum

gen. offensācŭli · gender neuter · decl. 2nd
a striking against; a tripping; stumbling
a striking against, a tripping, stumbling (postclass.).
Lit.: crebris offensaculis contusa crura, App. M. 9, p. 221, 3.—
a stumbling-block by extension
Transf., the object against which one stumbles, a stumbling-block: lapis ecce nostro fixus offensaculo est, Prud. Apoth. 45; so, adversarius nostris offensacula pedibus latenter opponit, Lact. Opt. D. 1.