Some retired people wear one near formal strip (7)
I believe the answer is:
nightie
'some retired people wear' is the definition.
'nightie' can be an answer for 'wear' (nightie is a kind of wear). I'm not sure about the 'some retired people' bit.
'one near formal strip' is the wordplay.
'one near' becomes 'nigh' (I've seen this before).
'formal strip' becomes 'tie' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'nigh'+'tie'='NIGHTIE'
Can you help me to learn more?
(Other definitions for nightie that I've seen before include "put on at end of day?" , "Bedtime attire" , "Bedtime habit" , "garment worn in bed" , "Sleepwear" .)