swelled head, have a

have a swelled head

To be conceited, arrogant, or self-aggrandizing. Cheryl has such a big head on her, all she ever talks about is herself. Janice has had a bit of a big head ever since she got that promotion.
See also: have, head, swell
Farlex Dictionary of Idioms. © 2015 Farlex, Inc, all rights reserved.

swelled head, have a

Be conceited, as in Winning all those prizes has not given her a swelled head, at least not yet. This idiom began as be swellheaded, first recorded in 1817. The present form dates from about 1860. For a synonym see big head.
See also: have, swell
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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