instinctively
instinctively
adverb
/ɪnˈstɪŋktɪvli/
by using instinct (= a natural quality that makes somebody/something behave in a particular way) rather than thought or training
He knew instinctively that something was wrong
e.g.
I didn't! I just reacted instinctively. 知らねえよ とっさに身体が動いた (
/yupeco/『ゴールデンカムイ』
2話)