keep one's eyes open vs keep one's eyes peeled

keep one's eyes open and keep one's eyes peeled both are verbs.

Word	Noun	Adjective	Verb	Adverb
keep one's eyes open	No	No	Yes	No
keep one's eyes peeled	No	No	Yes	No

As verbs, keep one's eyes open and keep one's eyes peeled are synonyms defined as:

keep one's eyes open and keep one's eyes peeled: pay attention; be watchful

Other synonyms of keep one's eyes open include keep one's eyes skinned.

keep one's eyes open (verb)	keep one's eyes peeled (verb)
pay attention; be watchful	pay attention; be watchful