Also found in: Dictionary, Thesaurus, Legal.
fasten (up)on someone or something
1. Lit. to take firm hold of someone or something. She fastened upon me and would not let me go until she finished speaking. I don't like people who fasten on me and ask a lot of questions.
2. Fig. to fix one's attention on someone or something. He fastened upon the picture for a brief moment and then turned away. The baby fastened on the television screen and watched it for many minutes.