mid-13c., of birds, "remain suspended in air;" also generally, "to float, rise to the surface;" from c. 1300 as "wait in readiness or expectation;" late 14c. as "loom protectively over," also figurative, of unknown origin. In Middle English often of ships at anchor, standing off a coast. Common 13c.-16c., then superseded by its derivative, hover (v.)).
"to rise up, to swell," 1590s, evidently from heave (v.), perhaps from its past tense form hove.