Synonyms for fasten

verb

1. To make something secure

   attach, lock, fix, tie, bind, lace, close, shut, affix, adhere, batten, tighten, secure, anchor, moor, strengthen, grip, zip, zip up, button, hook, shutter, grapple, hold, screw down, clasp, clamp, clutch, pin, nail, tack, bolt, rivet, screw, clinch, solder, set, weld, cement, glue, bond, wedge, jam, mortise, twist, fix firmly in position, chain, tether, lash, tie down, hold immovable, hold fixed, hold fast, make secure, make fast, entangle, stick, cinch, cement, bed, embed, catch, buckle, strap, knot, hitch, harness, bar, grasp, seal up; see also bind 1.

   Antonyms release*, loosen, unfasten.

2. To join two or more things

   couple, combine, connect; see join 1.

fasten, the somewhat more general word compared here, implies a joining of one thing to another, as by tying, binding, gluing, nailing, pinning, etc.; tie and bind are often interchangeable, but in discriminating use, tie specif. implies the connection of one thing with another by means of a rope, string, etc. which can be knotted to tie a horse to a hitching post, and bind suggests the use of an encircling band which holds two or more things firmly together to bind someone's legs; attach emphasizes the joining of two or more things in order to keep them together as a unit to attach one's references to an application