ruffle somebody's/a few feathers

ruffle a few feathers

To do something which annoys, irritates, or upsets other people. I know my presentation about the effects of climate change is going to ruffle a few feathers, but I have got to raise awareness about this issue! Harry's bombastic, arrogant demeanor tends to ruffle a few feathers, but he's a decent guy at heart.
See also: feather, few, ruffle
Farlex Dictionary of Idioms.

ruffle someone's feathers

Fig. to irritate or annoy someone. I didn't mean to ruffle his feathers. I just thought that I would remind him of what he promised us.
See also: feather, ruffle
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

ruffle feathers

COMMON If someone ruffles feathers, they say or do something which upsets or annoys people. His management style ruffled a few feathers. The tall Texan ruffled some English feathers with his remarks. Note: If a bird's feathers are ruffled they stand out from its body, for example because it is frightened or angry.
See also: feather, ruffle
Collins COBUILD Idioms Dictionary, 3rd ed.

ruffle somebody’s/a few ˈfeathers

(informal) annoy somebody by doing something that upsets and disturbs them: All this talk of a strike has clearly ruffled the management’s feathers. OPPOSITE: smooth (somebody’s) ruffled feathers
This refers to the way the wind disturbs the smooth surface of a bird’s feathers so that they stick out.
See also: feather, few, ruffle
Farlex Partner Idioms Dictionary
See also:
  • ruffle a few feathers
  • ruffle some feathers
  • direct (something) against (someone or something)
  • direct against
  • ruffle up
  • direct (something) at (someone or something)
  • direct at
  • disappoint
  • disappoint (someone or oneself) with (something)
  • disappoint with