Translation guide
How to express 'fasten' in Japanese depends on what you are fastening. Common actions include securing with a belt, tying, buttoning, locking, or attaching. The most natural choice varies by object and method.
To secure a seatbelt in a vehicle or airplane.
The standard way to say 'fasten your seatbelt'. 締める means to tighten or fasten.
Please fasten your seatbelt.
A more casual way to say 'put on your seatbelt'. する is a general verb for 'do', but here it means 'put on'.
Fasten your seatbelt when you get in the car.
To secure something using a buckle, clasp, hook, or similar fastener.
General verb for fastening with a clasp, buckle, pin, etc. Can be used for belts, bags, buttons, hair clips, etc.
I don't know how to fasten the buckle.
Please fasten the chin strap of your helmet.
Used when fastening involves tightening, like a belt or a strap. Often interchangeable with 留める for belts.
Used for fastening a hook or latch, like a chain lock on a door.
To close clothing or other items using buttons.
To close something using a zipper.
To secure something by tying, such as shoelaces, strings, or ropes.
To secure something with a lock and key or combination.
To attach one thing to another, often with screws, clips, or adhesive.
To attach, install, or fasten something to a surface or object. Used for shelves, parts, etc.
Fasten a shelf to the wall.
To fix, secure, or fasten in place. Often used in technical contexts.
Fasten the parts with screws.
To fasten with a fastener (generic). 留め具 means fastener (clip, clasp, etc.).
Fasten the documents with a clip.
留める (とめる) is for fastening with a clasp, buckle, button, or pin. 締める (しめる) is for tightening something like a belt or strap. 結ぶ (むすぶ) is for tying with string or laces. Choose based on the action.
There is no single Japanese verb that covers all meanings of 'fasten'. Using a generic verb like 固定する for clothing will sound unnatural. Always match the verb to the object and method.
Fasten a belt.
Fasten the door chain.
Fasten the luggage with rope.