Cydnewid, v. to interchange
Cydoddef, n. sympathy
Cydoed, n. a contemporary
Cydoes, a. coeval, coevous
Cydoesi, v. to contemporise
Cydofal, n. a mutual care
Cydol, a. complete, whole
Cydolrwydd, n. continuity
Cydradd, a. of equal degree
Cydraid, n. mutual want