unfasten
Americanverb (used with object)
-
unfastens,
present (3rd person singular)
-
unfastened,
past participle, past
-
unfastening
present participle
-
to release from or as from fastenings; detach.
-
to undo or open (something fastened).
verb (used without object)
-
unfastens,
present (3rd person singular)
-
unfastened,
past participle, past
-
unfastening
present participle
verb
Other Word Forms
Inflected Forms
Participles
Conjugated Forms
Present
-
unfastensimple
-
unfastenssimple
-
have unfastenedperfect
-
has unfastenedperfect
-
am unfasteningprogressive
-
are unfasteningprogressive
-
is unfasteningprogressive
-
have been unfasteningperfect progressive
-
has been unfasteningperfect progressive
Past
-
unfastenedsimple
-
had unfastenedperfect
-
was unfasteningprogressive
-
were unfasteningprogressive
-
had been unfasteningperfect progressive
Future
Etymology
Origin of unfasten
First recorded in 1175–1225, unfasten is from the Middle English word unfastnen. See un- 2, fasten
Explanation
When you unfasten something, you loosen or open it. You should wait to unfasten your seatbelt until the car has completely stopped. To fasten is to hook, close, or latch something, and to unfasten it is to undo it. You might unfasten your dog's leash so she can run free on the beach or unfasten the snaps and buttons on your jacket so you can take it off. You can also unfasten your ponytail, letting your hair down, or unfasten the latch on a gate. The Old English root word is fæstnian, "make fast or firm."
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
See Examples For:
For 12 days, we shared every moment and, surrounded by the kind of beauty only a remote bay in the Pacific could afford, I felt something unfasten in my chest.
From Los Angeles Times ● Mar. 8, 2024
To serve the cheesecake, run a knife around the outer edge to loosen it from the pan, then carefully unfasten the sides of the pan and transfer the cheesecake to a cake plate or stand.
From Fox News ● Dec. 16, 2021
Operators are supposed to unfasten all of the seat belts after each ride so the next load of people can be buckled in.
From Seattle Times ● Sep. 25, 2021
Turn off the heat, allow the pressurized steam to escape, then unfasten the lid and check for doneness; you want your beans to be very tender and quite creamy.
From Washington Post ● Jun. 3, 2018
Annabeth and the Ares campers were trying to unfasten her helmet.
From "The Last Olympian" by Rick Riordan
![]()
The bearded guy in front of us unfastens his earflaps and says, chuckling, “Haven’t you guys ever stood in line for beer before?”
From Washington Post ● Sep. 6, 2017
Home for the busy man about Brazil these days is where he unfastens his seat belt.
From Time Magazine Archive
![]()
One Atlanta man unfastens his seat belt, and turns off his hearing aid, as soon as he starts his new Impala.
From Time Magazine Archive
![]()
I give it a press and the clasp unfastens.
From "Amari and the Night Brothers" by B.B. Alston
![]()
Vivian unfastens the silk loops from their hooks at each side of the casing, letting the heavy paisley curtains fall across the glass.
From "Orphan Train" by Christina Baker Kline
![]()
"At first, I thought I was going to die. I managed to open my eyes, unfastened my seat belt and tried to exit the plane."
From BBC ● Jun. 13, 2025
Sempill and Dollfus, whose belts were unfastened, were flung out.
From Slate ● Aug. 2, 2022
His true devotion to the mouse was hidden just underneath: He unfastened the shirt’s top button to reveal a tattoo on his chest of Mickey Mouse flying a biplane.
From Los Angeles Times ● May 11, 2022
By magnifying the grooves, engineers confirmed the “backed off” or unfastened nut hadn’t been tightened enough, which led to other parts misaligning, then a loss of lubricating oil.
From Seattle Times ● Mar. 15, 2022
They have layers of tulle and are propped up underneath with crinolines, and I worry about the hooks coming unfastened.
From "Cat's Eye" by Margaret Atwood
![]()
Kondo brought garments to life, like kites in the sky with voluminous silhouettes created by fastening and unfastening buttons.
From Seattle Times ● Jun. 20, 2024
He must have disembarked in Cold Lake, where they had stopped so briefly that Vaughn hadn’t even bothered unfastening her seat belt.
From Slate ● Jul. 30, 2022
Anita Klemencic of Slovenia stayed upright for a good long while, unfastening her skis more quickly than do some.
From Washington Post ● Feb. 10, 2022
Fastidiously spend a couple of minutes unfastening all the straps before you can sit down?
From The Guardian ● Sep. 19, 2019
I set Ma’s sneakers in front of her, and she slips them on without unfastening the Velcro straps.
From "Dragons in a Bag" by Zetta Elliott
![]()
Definitions and idiom definitions from Dictionary.com Unabridged, based on the Random House Unabridged Dictionary, © Random House, Inc. 2023
Idioms from The American Heritage® Idioms Dictionary copyright © 2002, 2001, 1995 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company.