to attach firmly or securely in place; fix securely to something else.

to make secure, as an article of dress with buttons, clasps, etc., or a door with a lock, bolt, etc.

to enclose securely, as a person or an animal (usually fol. by in )

to fasten a monkey in a cage.

to attach, associate, or connect

to fasten a nickname on someone.

to direct (the eyes, thoughts, etc.) intently

to fasten one's eyes on a speaker.

to become fast, fixed, or firm.

to close firmly or securely; lock

This clasp won't fasten.

to take a firm hold; seize (usually fol. by on or upon )

to fasten on an idea.

to focus attention; concentrate (usually fol. by on or upon )

His gaze fastened on the jewels.

verb

detach , disconnect , loosen , open , release , unchain , unfasten , unlink , unlock

verb

adhere , affix , anchor , attach , band , bar , batten , belt , bind , bolt , bond , brace , button , catch , cement , chain , cleave , close , cohere , connect , couple , embed , establish , fix , freeze to , girth , glue , grip , hitch , hitch on , hold , hook , hook up , implant , infix , jam , knot , lace , leash , link , lock , lodge , make firm , moor , mortise , nail , rivet , rope , screw , seal , set , settle , solder , stay put , stick , strengthen , string , tack on , tag , tie , tighten , truss , unite , wedge , weld , clip , secure , tie up , entrench , ingrain , root , assign , blame , impute , pin on , place , annex , append , barricade , bend , clamp , clasp , clinch , cling , direct , focus , join , latch , padlock , paste , pin , sew , staple , strap , tether , wire