Meaning to return number 1 metal? I'd accept iron (10)

'meaning' is the definition.
(I know that meaning can be written as definition)

'return number 1 metal? i'd accept iron' is the wordplay.
'return' shows that the letters should be reversed in order.
'number' becomes 'no' (abbreviation for 'number').
'i metal?' becomes 'itin' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'accept' means one lot of letters goes inside another.
'iron' becomes 'Fe' (Fe is the chemical symbol for iron).
'no'+'itin'+'id'='noitinid'
'noitinid' placed around 'fe' is 'noitinifed'.
'noitinifed' written backwards gives 'DEFINITION'.

'to' acts as a link.

Can you help me to learn more?