Noun
acquired behavior that is practiced so long it seems innate
Source: WordNetWith the eye in a natural state sight follows necessarily ... In the same way the life of blessedness is as a familiar second nature to those who have kept clear the senses of the soul. Gregory of Nyssa
Custom is almost second nature. Plutarch
Now, performing is second nature and I love every second of it. It is a very emotional thing when I can't play a song; maybe I'm hitting on something that I don't want to deal with. All of it is so personal. It is like therapy. Vanessa Carlton
Habit is a second nature. Russian Proverb
Habit becomes second nature. Kurdish Proverb
Habbit is a second nature. English Proverb