From Longman Dictionary of Contemporary Englishsneak a look/glance/peeksneak a look/glance/peekLOOK ATto look at something quickly and secretly, especially something that you are not supposed to see He sneaked a look at her. → sneak
Examples from the Corpus
sneak a look/glance/peek• Men sneak looks all the time!• Only the men would sneak glances at her, admiring the shapely figure showing in the plain uniform.• I sneaked a look at my medical report; slow heartbeat, low metabolism.• The chairman sneaks a look at some of the messages on Doreen's card.• Occasionally they sneak glances at the businessmen -- who look back at them in mutual amazement and fear.• Just before we left, I raised up to straighten my coat and sneaked a look at the McLaren girl.• Babur sneaks a look at the policewoman.• I sneaked a look behind as we went off in a cloud of dust. 