Inactivity (6)
'inactivity' is the definition.
(I've seen this in another clue)
This is all the clue.
(Other definitions for inertia that I've seen before include "Unwillingness to move" , "I earn it (anag.)" , "Passiveness" , "Immobility" , "Torpor" .)
'inactivity' is the definition.
(stasis is a kind of inactivity)
This is the entire clue.
(Other definitions for stasis that I've seen before include "Inactivity or stoppage of circulation" , "Total lack of movement" , "No progressive state" , "absence of change" , "State in which blood-flow is stopped" .)
(Other definitions for torpor that I've seen before include "Extreme lethargy" , "State of mental or physical inactivity" , "State of dullness" , "Listlessness" , "State of sluggish somnolence" .)