Utas \U"tas\, n. [OF. huitieves, witieves, witaves, oitieves, pl. of huitieve, witieve, etc., eighth, L. octavus. See {Octave}, n.] [Written also {utis}.] [1913 Webster] 1. (O. Eng. Law) The eighth day after any term or feast; the octave; as, the utas of St. Michael. --Cowell. [1913 Webster] The marriage was celebrated and Canterbury, and in the utas of St. Hilary next ensuing she was crowned. --Holinshed. [1913 Webster] 2. Hence, festivity; merriment. [Obs.] --Shak. [1913 Webster]