- uncoerced, unforced, willing - not brought about by coercion or force; "the confession was uncoerced"
Antonyms: involuntary, nonvoluntary, unvoluntary (indirect, via voluntary)
- unforced, unstrained - not resulting from undue effort; not forced; "a voice with a pleasingly unforced quality"; "his playing is facile and unstrained"
Antonym: effortful (indirect, via effortless)