Sustentaculum, li, n g. That which sustaineth or beareth vp.
Lewis and Short: Latin dictionary
sustentācŭlum, i, n. [sustento], a prop, stay, support.I.Lit. (post-Aug. and very rare): sustentaculum, columen, Tac. H. 2, 28.—II.Transf., sustenance, nourishment: sustentaculum sumptuosum corporis, Aug. Mor. Eccl. Cath. 33.