Womanizer is a guy who gets every girl to like him. a gutless and senseless man who treats every girl like they’re the girl for him, then lets them down by having MANY other girls on the side.

Womanizer就是指到处讨好女孩子，让她们以为自己就是他生命中那个重要的她；可结果，他却是个没心没肺、没有真情实感，身边有很多个女朋友的“洋葱男”。
A womanizer is compared to an onion because he generally uses layer after layer of sweet words and other deceiving tactics to seduce a woman. But in the end, the romance comes to nothing, leaving the woman in tears when she finds out the truth.
之所以称他们为“洋葱男”，是因为他们通常用一层又一层的甜言蜜语和各种花招吸引女性。可最终结果往往是，女性竹篮打水一场空，唯有泪千行。