Third-person singular simple present indicative form of fasten.(verb)
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Use "fastens" in a sentence
"Realism is a hard-worked term, but it may be taken to imply that the overflowing vitality of which poetry is one expression fastens with peculiar eagerness upon the visible and tangible world about us and seeks to convey that zest in words."
"In "Mrs. Nixon," the novelist Ann Beattie fastens on that straightforward story and deconstructs it to the ground."
"The zipper fastens for security (I have twice had items stolen in flight); the bag will pack flat should you want to pack it on your return (because you had to have that handbag from Prada's Via Montenapoleone store); and because it is soft and pliable, depending upon what you put in it, it will double as a pillow (I know, because I've used mine for this and many other purposes, including a footrest.)"