set in one's ways, be

be set in (one's) ways

To be habituated to one's routine or usual behavior, often to the point of being unwilling to change any aspect of it. Grandma will never retire—she's been a teacher for 50 years and is totally set in her ways. You'll never convince him to change, he's too set in his ways now.
See also: set, way
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

set in one's ways, be

Be inflexible, fixed in one's habits, as in She's too set in her ways to go out and buy a dog. This idiom uses set in the sense of "in a rigid position," a usage dating from about 1300.
See also: set
The American Heritage® Dictionary of Idioms by Christine Ammer. Copyright © 2003, 1997 by The Christine Ammer 1992 Trust. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
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