#Thaive# is a two-year-old ewe. Wright gives _theave_ or _theeve_
as the commoner forms, and in the Paston letters it is _theyve_, which
perhaps confirms _thaive_, rhymed here with 'rave'. Certainly it is most
advisable to avoid _thieves_, the plural of thief, although _O.E.D._
allows this pronunciation and indeed puts it first of the alternatives.