Tense one running and dancing (8)
I believe the answer is:
'dancing' is the definition.
(tangoing is a kind of dancing)
'tense one running' is the wordplay.
'tense' becomes 't' (abbreviation used in many dictionaries).
'one' becomes 'an' (an apple is one apple).
'running' becomes 'going' ('go' can be a synonym of 'run').
'and' is the link.
(Other definitions for tangoing that I've seen before include "what obsessive sunbather dreads?" , "Dancing" , "Taking steps" .)