Drink often preceded by one very similar element (7)
I believe the answer is:
isotope
'similar element' is the definition.
The answer and definition can be both substances as well as being singular nouns.
Perhaps there's a link between them I don't understand?
'drink often preceded by one very' is the wordplay.
'drink often' becomes 'tope' (synonyms. I am not sure about the 'often' bit.).
'preceded by' is a charade indicator (letters next to each other).
'one' becomes 'i' (Roman numeral).
'very' becomes 'so' (both can mean 'extremely').
'i'+'so'='iso'
'tope' after 'iso' is 'ISOTOPE'.
Can you help me to learn more?
(Other definitions for isotope that I've seen before include "Oops, tie up the atom" , "Variant element form" , "Form of atomic nucleus" , "O, is poet involved in chemical element?" , "Type of atom, maybe radioactive" .)