Cysdadlaeth, n. competition
Cysdadliad, mutually disputing
Cysdadlu, v. to vie; to debate
Cystadlwr, n. a competition
Cysdawd, n. a butting together
Cysdedlydd, n. a competitor
Cysdodi, v. to place in custody
Cysefin, a. primary, primitive
Cysefino, v. to originate
Cysefiniad, n. originality