boar UK /bɔː(ɹ)/US /boɹ/ noun5 •A wild boar (Sus scrofa), the wild ancestor of the domesticated pig. •A male pig."Bull hogs," or boars, which are uncastrated male pigs, tend to have a dark, gamy flesh not appreciated by everyone. — 2000 •A male boar. •A male bear. •A male guinea pig. formsboars