The Collaborative International Dictionary of English v.0.48:
Sudra \Su"dra\ (s[=oo]"dr[.a]), n. [Skr. [,c][=u]dra.] The lowest of the four great castes among the Hindoos. See Caste. [Written also Soorah, Soodra, and Sooder.] [1913 Webster]WordNet (r) 3.0 (2006):
Sudra n 1: a member of the lowest or worker Hindu caste [syn: Shudra, Sudra] 2: the lowest of the four varnas: the servants and workers of low status [syn: sudra, shudra]