Definition of fasten onto
: to grip and tightly hold (something) The stranger fastened onto my arm and wouldn't let go. —often used figuratively Once he fastens onto a subject he just won't let it drop.
Word by Word Definitions
: to attach especially by pinning, tying, or nailing
: to make fast and secure
: to fix firmly or securely
: to a position on
: in or into a state of awareness about
: used as a function word to indicate a set each element of which is the image of at least one element of another set
: mapping elements in such a way that every element in one set is the image of at least one element in another set
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