Put into words seeing Romeo occupying stage (6)
I believe the answer is:
phrase
'put into words' is the definition.
(I've seen this before)
'romeo occupying stage' is the wordplay.
'romeo' becomes 'r' (phonetic alphabet: alpha, bravo, charlie etc.).
'occupying' means one lot of letters goes inside another.
'stage' becomes 'phase' (phasing is a kind of staging).
'r' put inside 'phase' is 'PHRASE'.
'seeing' is the link.
(Other definitions for phrase that I've seen before include "few words from a tourist guide?" , "a certain expression" , "Group of words forming part of a sentence" , "Group of words/notes" , "Expression without a verb" .)