Synonyms for in-fallible
- authoritative
- flawless
- foolproof
- unbeatable
- acceptable
- accurate
- agreeable
- apodictic
- certain
- correct
- effective
- effectual
- efficacious
- efficient
- exact
- faultless
- handy
- helpful
- impeccable
- incontrovertible
- inerrable
- inerrant
- omniscient
- perfect
- positive
- reliable
- satisfactory
- satisfying
- sure
- surefire
- true
- trustworthy
- undeceivable
- unfailing
- unimpeachable
- unquestionable
- useful
MOST RELEVANT
Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the
Philip Lief Group.