Synonyms for Quash:

n.

kill off, hold back, shut off, squash, quell, stamp out, squeeze out, interfere with, defeat, cut into. fence in, control, hamper, infringe, fetter, tie down, limit, pen in, constrain, bind. quash (noun)
keep down, invalidate, reduce, repress, nullify, subjugate, subdue, void, avoid, annul.

v.

abolish (verb)
nullify, stamp out.
black out (verb)
hold back.
quash (verb)
invalidate, subdue, repress, void, squelch, put the lid on, quell, put down, extinguish, annul, quench, crush, squash.
social (verb)
subdue, reduce, subjugate, repress, keep down.

Other synonyms:

squash, squelch. quell. extinguish. quench. crush. silence
choke off, keep down.
Other relevant words:
defeat, acquittal, put the lid on, infringe, extinguish, fetter, award, choke off, quench, hamper, win, hold back, bar, control, squash, citation, shut off, constrain, quell, limit, crush, squelch, stamp out, charge, acquit, bind.

Usage examples for quash

  1. The time has come for me to hold in scorn The murmur of distinguished nobodies, And quash pernicious custom. – Boris Godunov A Drama in Verse by Alexander Pushkin Rendered into English verse by Alfred Hayes