a. Obs.1 [UN-1 7.] Undoubtful, undoubted.

1

c. 1374.  Chaucer, Boeth., V. pr. i. (1868), 149. Syn it nis nat to douten of þe þinges folwynge whan euery side of þi disputisoun shal be stedfast to me by vndoutous [L. indubitata] feiþ.

2