1) Aspect 2) Durative aspect 1) Imperfective 
continuing; not completed; undergoing transformation
• (a.) Continuing; not completed; implying duration.
Dur'a·tive adjective Continuing; not completed; implying duration. « Its durative tense, which expresses the thought of it as going on.» J. Byrne. 
[n] - the aspect of a verb that expresses its duration
durative aspect noun the aspect of a verb that expresses its duration
noting or pertaining to a verb aspect expressing incomplete or continued action. Beat and walk are durative in contrast to strike and step.