Girl takes two articles (4)
I believe the answer is:
thea
'girl' is the definition.
'two articles' is the wordplay.
'two articles' can mean two substitutions for 'article'.
'article' becomes 'the' (the 'definite article' part of speech**).
'article' becomes 'a' (indefinite article).
'the'+'a'='THEA'
'takes' acts as a link.
(Other definitions for thea that I've seen before include "... Girl" , "Plant" , "Girl's name, tea genus" , "evergreen shrubs?" , "Female name meaning 'goddess'" .)