In the trunk area, red blazer is snug, restricting one in everything (4,5)
I believe the answer is:
tail light
'in the trunk area red blazer' is the definition.
I know nothing about this answer so I cannot judge whether it can be defined by this definition.
'snug restricting one in everything' is the wordplay.
'snug' becomes 'tight' (similar in meaning).
'restricting' means one lot of letters goes inside another.
'one' becomes 'i' (Roman numeral).
'in' means one lot of letters goes inside another.
'everything' becomes 'all' (all things).
'i' going within 'all' is 'aill'.
'tight' going around 'aill' is 'TAIL-LIGHT'.
'is' acts as a link.
Can you help me to learn more?
(Other definitions for tail light that I've seen before include "car shows it braking" , "motoring requisite" , "followers'll see it" , "fitting on back of bike?" , "rear lamp" .)