Female pens revolutionary opening lines (7)
I believe the answer is:
strophe
'lines' is the definition.
(group of lines of poetry)
'female pens revolutionary opening' is the wordplay.
'female' becomes 'she' (I've seen this before).
'pens' indicates putting letters inside.
'revolutionary opening' becomes 'trop' (I can't justify this - if you can you should give a lot more credence to this answer).
'she' placed around 'trop' is 'STROPHE'.
(Other definitions for strophe that I've seen before include "Division of choral ode" , "Section of Greek choral ode; stop her (anagram)" , "song for chorus" , "Section of lyric poem" , "Part of a lyric poem" .)