To womanize means, of a man, to keep having sexual relationships with many different women, one after another or at the same time — usually with the sense that he is not serious about any of them and often that he is cheating on a wife or partner. The word is only ever used about men, and it always carries disapproval; nobody says it about himself with pride, and there is no matching word used about women. In practice you will almost never meet the plain verb 'womanize' in modern English — it sounds bookish and old. What you do meet constantly is its two children: the noun 'womanizer' (a man who does this) and the '-ing' form used as an adjective or a noun, as in 'his drinking and womanizing' or 'a hard-drinking, womanizing actor'. Note the British spelling 'womanise' is equally correct; British and American writing differ only in the s/z. The tone is worth feeling carefully: it is disapproving but slightly old-fashioned and even a bit amused, the way a newspaper writes about a film star from the 1960s. For serious modern criticism of a man's behaviour, English now uses plainer words.

（男人）玩弄女性、到處拈花惹草（貶意）