RichThesaurus
nonchalant
vs
unvolitioned
nonchalant
adj
Indifferent; unconcerned; behaving as if detached.
Casually calm and relaxed.
unvolitioned
adj
Involuntary.
How often have the words
nonchalant
and
unvolitioned
occurred in a corpus of books?
(source:
Google Ngram Viewer
)