Englishogle
verb
he'd been ogling her ever since she'd entered the room:
leer at, stare at, gaze at, eye, make eyes at, make sheep's eyes at;
informal eye up, give someone the glad eye, give someone a/the once-over, lech after/over, undress with one's eyes, give someone the come-on;
British, informal gawp at, gawk at;
Australian, New Zealand, informal perv on.