Definition of fasten on
: to direct (something, such as one's eyes or attention) to (something) They fastened their eyes on the distant ship. She fastened her attention on the problem. They had fastened the blame on the wrong man. She fastened (all) her hopes on getting the job.
Word by Word Definitions
: to attach especially by pinning, tying, or nailing
: to make fast and secure
: to fix firmly or securely
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