Other forms: lecherously
To be lecherous is to be full of strong sexual desire and to act on it, usually in an unpleasant way.
People who are lecherous are kind of obsessed with sex — they can't stop thinking about it or having it. This is a word that is used more often to describe men than women: lecherous men are called lechers. There is also a creepy flavor to this word. If you describe someone as lecherous, it usually isn't a compliment. A common use is talking about a lecherous old man who hits on younger women.