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Definitions

conscientious

[kon-shee-en-shuhs, kon-see-] / ˌkɒn ʃiˈɛn ʃəs, ˌkɒn si- /
ADJECTIVE
thorough, careful
Synonyms
STRONGEST
diligent fastidious fussy meticulous painstaking
WEAK
complete exact exacting faithful hanging in hanging tough heart and soul into heedful minding p's and q's particular playing safe punctilious punctual reliable tough walking on eggs
Antonyms
STRONGEST
careless indifferent uncritical undemanding
WEAK
corrupt dishonest inexact irresponsible uncareful unconscientious unjust unscrupulous vulgar
ADJECTIVE
moral, upright
Synonyms
STRONGEST
honest honorable principled responsible scrupulous strict
WEAK
conscionable high-minded high-principled incorruptible just pious right straightforward true
Antonyms
STRONGEST
untrustworthy
WEAK
careless corrupt dishonest immoral inexact irresponsible uncareful unconscientious unjust unscrupulous vulgar

From Roget's 21st Century Thesaurus, Third Edition Copyright © 2013 by the Philip Lief Group.