Pronunciation: (är'sis), [key]
—pl. -sesPronunciation: (-sēz). [key]
1. Music.the upward stroke in conducting; upbeat. Cf. thesis (def. 4).
a. the part of a metrical foot that bears the ictus or stress.
b. (less commonly) a part of a metrical foot that does not bear the ictus. Cf. thesis (def. 5).
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.