another meaning of 'heat-seeking missile'

Well, Lindsay’s “M.O.” is to get her hooks into powerful, married men. Look. She’s a heat-seeking missile. And Eddie has no heat. Your friend, Alex, does.

FYI, Lindsay is a gold digger.

I googled 'heart-seeking missele' and it says it's a slang that describes male's genitals. But I don't think that's not what the speaker wanted to say.

Is there another meaning of 'heart-seeking missele'? Like a gold digger? Or it's just figure of speech?

(My native language is not English. Please be kind to me. :-))

Your looking at the "Urban Dictionary" and those are not official definitions at all. Those definitions are created by random people trying to be funny. Heat seeking missile is just what it says. Its a missile used in war, not male genetalia. By the way, im assuming you were trying to google "heat seeking missile" not "heart seeking missile". There is no such thing as heart seeking missile.