strict or thorough in the performance of duty

a faithful worker.

true to one's word, promises, vows, etc.

steady in allegiance or affection; loyal; constant

faithful friends.

reliable, trusted, or believed.

adhering or true to fact, a standard, or an original; accurate

a faithful account; a faithful copy.

Obsolete . full of faith; believing.

the faithful,

the believers, esp. members of a Christian church or adherents of Islam.

the body of loyal members of any party or group.

adjective

dishonest , disloyal , false , inconstant , treacherous , unfaithful , unreliable , untrue , different , inaccurate , inexact , uncertain

adjective

affectionate , allegiant , ardent , attached , behind one , circumspect , confiding , conscientious , constant , dependable , devoted , dutiful , dyed-in-the-wool * , enduring , fast , firm , genuine , hard-core * , honest , honorable , incorruptible , loving , obedient , on the level * , patriotic , resolute , scrupulous , sincere , staunch , steadfast , steady , straight , string along with , sure , tried , tried and true , true , true-blue * , trustworthy , trusty , truthful , unchanging , unswerving , unwavering , upright , veracious , close , credible , exact , just , lifelike , precise , right , similar , strict , undistorted , veridical , liege , loyal , authoritative , convincing , valid , full , rigorous , correct , accurate , leal , pious , reliable , stanch