know by sight

Related to know by sight: known by sight

know (someone or something) by sight

To recognize someone or something based solely on appearance (without knowing any other information, such as a name, etc.). Even after working there for a year, there were still some co-workers I only knew by sight. I'd know the place by sight, but I don't think I could tell you how to get there.
See also: by, know, sight
Farlex Dictionary of Idioms.

know someone by sight

to recognize a person's face, but not know the name. I'm afraid I don't know her by sight. I know all my employees by sight.
See also: by, know, sight
McGraw-Hill Dictionary of American Idioms and Phrasal Verbs.

know by sight

Recognize someone or something by appearance but not know the name or other details. For example, I know a lot of people by sight from the tennis courts. [1200s]
See also: by, know, sight
The American Heritage® Dictionary of Idioms by Christine Ammer.
See also:
  • know (someone or something) by sight
  • know somebody by sight
  • feud
  • feud about (someone or something)
  • feud with (someone)
  • feud with (someone) over (someone or something)
  • feud over (someone or something)
  • honor (someone) with (something)
  • honor with
  • get something straight