The Collaborative International Dictionary of English v.0.48:
A-sea \A-sea\, adv. [Pref. a- + sea.] On the sea; at sea; toward the sea. [1913 Webster]WordNet (r) 3.0 (2006):
asea adv 1: in the direction of the sea; "the sailor looked seaward" [syn: seaward, seawards, asea]