Tin with one very strong smell (5)
I believe the answer is:
sniff
'smell' is the definition.
(sniffing is a kind of smelling)
'tin with one very strong' is the wordplay.
'tin' becomes 'sn' ('Sn' can be a synonym of 'tin').
'with' says to put letters next to each other.
'one' becomes 'i' (Roman numeral).
'very strong' becomes 'ff' (I am not sure about the 'very' bit.**).
'sn'+'i'+'ff'='SNIFF'
Can you help me to learn more?
(Other definitions for sniff that I've seen before include "Slight suspicion (perceived though the nose?)" , "Chance" , "Inhale audibly through the nose" , "express one's displeasure" , "What tracker dogs do" .)