First person to hear or look at closely (3)
I believe the answer is:
eye
'look at closely' is the definition.
I can't tell whether this definition defines the answer.
'first person to hear' is the wordplay.
'first person' becomes 'I' (first-person pronoun).
'to hear' shows a homophone (sound like).
'i' sounds like 'EYE'.
'or' acts as a link.
Can you help me to learn more?
(Other definitions for eye that I've seen before include "Oculus" , "View" , "Perception" , "Observe narrowly" , "Middle of storm" .)