only have eyes for (someone)

to be interested in or attracted to only one person.

You've no need to be jealous. I only have eyes for you.

• by a mile
• by and large
• by a nose
• by any stretch of the imagination
• by a whisker
• by definition
• by degrees
• by dint of
• by dint of something
• by fair means or foul
• by far
• by hand
• by heart
• by hook or by crook
• by leaps and bounds
• by mistake
• by no means
• by rote
• by the back door
• by the book
• by the dozen
• by the name
• by the name of
• by the same token
• by the seat of pants