Manubrium \Ma*nu"bri*um\, n.; pl. L. {Manubria}, E. {Manubriums}. [L., handle, fr. manus hand.] 1. (Anat.) A handlelike process or part; esp., the anterior segment of the sternum, or presternum, and the handlelike process of the malleus. 2. (Zo["o]l.) The proboscis of a jellyfish; -- called also {hypostoma}. See Illust. of {Hydromedusa}.