Ymbwyll, n. consideration
Ymbwys, n. a self-pressure
Ymbwyth, n. competition
Ymchwel, n. return, reverse
Ymchweliad, n. a returning
Ymchwelyd, v. to return
Ymchwyddo, v. to swell one’s self
Ymdaclu, v. to trim one’s self
Ymdaenu, v. to self-expand
Ymdaeru, v. to dispute together