know (someone/something) by sight

to recognize someone or something.

I've never spoken to him, but I know him by sight.

Usage notes: usually used to suggest that you know what someone looks like but not what type of character someone has

• give someone the heave ho
• give someone the heebie-jeebies
• give someone their due
• give someone their head
• give someone their marching orders
• give someone their walking papers
• give someone the jitters
• give someone the kiss of life
• give someone the nod
• give someone the old heave ho
• give someone the once-over
• give someone the push
• give someone the right of first refusal
• give someone the right to first refusal
• give someone the rough side of tongue
• give someone the rough side of your tongue
• give someone the runaround
• give someone the sack
• give someone the shaft
• give someone the shits
• give someone the shivers
• give someone the slip
• give someone the time of day
• give someone the willies
• give someone the works