adjective
sane
SAYN/seɪn/
Sound in mental judgment.
The adult makes a sane decision after calmly comparing the evidence.

Etymology
Latin sanus covered bodily health as well as soundness of mind. English sane became chiefly a word for mental soundness through its contrast with insane, which referred to mental condition.
In context
a perfectly sane man not intimidated by religious or other delusions could always render himself perfectly secure from detection
More examples
- He offers a sane solution to a complicated problem.
- We need a saner schedule that leaves time for rest.
- She is perfectly sane, even if you disagree with her.
Forms
sane · saner · sanest
sanity noun — The state of being mentally sound.
sanely adverb — In a rational and sensible manner.