4. To engage in (indiscriminate) sexual promiscuity.
5. To search promiscuously for sexual partners.
(1) Seth (John Halliday) and Tracy (Katharine Hepburn) in The Philadelphia Story (1940):
-- Seth Lord: ' What most wives fail to realise is that their husband's philandering has nothing to do with them.'
-- Tracy Lord: ' Oh? Then what has it to do with? '
-- Seth Lord: ' A reluctance to grow old, I think.'
(2) Dick Pepper (Gig Young) explaining to his friend Augie Pool (Richard Widmark) the vicious circle of guilt of the philandering husband in The Tunnel of Love (1958):
-- Dick: ' Every time it's over I have a terrific sense of guilt.'
-- Augie: ' Oh, but you wait until it's over, hum? '
-- Dick: ' Sure. I feel I deserve this guilt. When I don't have it I'm uncomfortable so I try to recapture the guilt by chasing around.'
-- Augie: ' So why do you keep chasing around then if it's that much trouble? '
-- Dick: ' I've got to get back to that feeling of guilt. (...) I have to suffer for chasing around.'