headward / headword [ˈhɛdwɜrd]
headward – adv., adj. & n. – adv. – 1. towards the head; 2. in the direction of the source of a stream; adj. – occurring at or near the head; n. – feudal service consisting in acting as a guard to the lord
headword – n. – a wording forming a heading, e.g., of an entry in a dictionary or encyclopedia