The Collaborative International Dictionary
Twifallow
Twifallow \Twi"fal`low\, v. t. [imp. & p. p. Twifallowed; p. pr. & vb. n. Twifallowing.] [AS. twi- (see Twice) two + fallow.] To plow, or fallow, a second time (land that has been once fallowed).
Wiktionary
twifallow
n. (context obsolete English) The process of twifallowing land. vb. (context transitive obsolete English) To plow a second time, as fallow land, to prepare it for seed.