What does Hassan mean?
From Arabic حسن (ḥasan) 'handsome, beautiful, good', from the root ḥ-s-n which also gives husn ('beauty'). The sense spans moral goodness and physical beauty.
What does Zayd mean?
From the root z-y-d (ز-ي-د, 'to increase, to grow, to add'), meaning 'growth, increase, abundance'. Borne by Zayd ibn Harithah, a companion and the adopted son of the Prophet. Also spelled Zaid.