Word or sentence (4)
I believe the answer is:
term
I believe this clue is a double definition.
'word' is the first definition.
(I've seen this before)
'sentence' is the second definition.
(thesaurus)
'or' is the link.
(Other definitions for term that I've seen before include "A fixed or limited time - or an expression" , "Word or expression and period of time" , "Semester" , "Word; limited period" , "Scholastic period" .)