1. Declare invalid
   - annul, quash, void, avoid, nullify 
2. Make invalid for use
   - cancel 
3. Show to be invalid
   - nullify 
4. Take away the legal force of or render ineffective
   "invalidate a contract"
   - void, vitiate

Derived forms: invalidates, invalidating, invalidated

See also: invalidation, invalidator

Type of: alter, cancel, change, contradict, mark, modify, negate, score, strike down

Antonym: validate

• generalized anxiety disorder
• generalized epilepsy
• generalized seizure
• generally
• generally accepted accounting principles
• generalship
• generate
• generation
• generation gap
• generation X
• shunt
• shunt circuit
• shunter
• shush
• shut
• shut away
• shut in
• shut off
• shut one's mouth
• shut up
• shutdown
• Shute
• shuteye
• shutout
• shutter