Expression from Romeo entering stage (6)
I believe the answer is:
phrase
'expression' is the definition.
(I know that expression can be written as phrase)
'romeo entering stage' is the wordplay.
'romeo' becomes 'R' (phonetic alphabet: alpha, bravo, charlie etc.).
'entering' means one lot of letters goes inside another.
'stage' becomes 'phase' (both can mean a part or period of something).
'r' put into 'phase' is 'PHRASE'.
'from' is the link.
(Other definitions for phrase that I've seen before include "Sequence of words" , "Group of words within a sentence" , "Group of words without a verb" , "Present" , "Seraph (anag.)" .)