In many words taken from L or OF, or from both sources, as conceiven, concepcioun; confermen, -firmen, -firmacioun; confessen, -fessioun, -fessour; conqueren, -querour, -queste. Since the L or OF simplex is only rarely adopted into ME and the meaning of the historically primary morpheme in such sets as con-ceiven, de-ceiven, per-ceiven is obscure, the prefix con- has only the vaguest meaning in ME. Hence it is not productive in ME, though occasionally translators, hard-pressed for a precise English equivalent of a Latin expression, do coin such hybrids as con-fere colleague, con-gaderen collect.