second nature

American  

noun

1. an acquired habit or tendency in one's character that is so deeply ingrained as to appear automatic.

   Neatness is second nature to him.

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second nature British  

noun

1. a habit, characteristic, etc, not innate but so long practised or acquired as to seem so

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second nature Idioms  

1. A habit or mode of behavior so long practiced that it seems innate, as in Driving in heavy traffic is second nature to Chris. This expression is a shortened form of an ancient proverb, Custom (or usage) is a second nature, first recorded in 1390. It alludes to the fact that very frequently repeating something makes it seem completely natural or inborn.

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Etymology

Origin of second nature

First recorded in 1655–65

Example Sentences

For example, cybersecurity training could teach simple, practiced routines and focus on creating habits, so that avoiding risky links becomes second nature.

From The Wall Street Journal

But in an organization built on service and community engagement, second nature quickly kicked in.

From Los Angeles Times

She did all this calmly, without seeming effort, for caring for children in this way was second nature to her and left her mind free to wander.

From Literature

He's still a teenager whose pace and ability to ghost past defenders is second nature to him.

From BBC

The idea is that once it comes to gametime, passes can come from any direction and hauling them in becomes second nature because it’s such a familiar process.

From The Wall Street Journal