Have a thing for somebody/something Definition 1 of 3Pro Tip 1/3Romantic Connotation Usually implies romantic interest, more than just a casual liking. Ever since we met, I think I've had a thing for her. Pro Tip 2/3Subtle Admittance Indicates one's preference subtly without being overtly direct. I would say I've got a thing for jazz music, don't you think? Pro Tip 3/3Casual Phrase It's an informal expression mostly used among friends or in casual contexts. She mentioned she has a thing for guys who play guitar.