gratuitous

Synonyms: chargeless complimentary costless for nothing gratis spontaneous unasked-for unpaid voluntary willing

Antonyms: costly expensive

Synonyms: assumed baseless bottomless causeless groundless indefensible inessential needless reasonless supererogatory superfluous uncalled-for unessential unfounded unjustified unmerited unprovoked unsupportable unwarranted wanton

Antonyms: deserved needed reasonable warranted