Active (4)
'active' is the definition.
(I know that active can be written as alive)
This is all the clue.
(Other definitions for alive that I've seen before include "Teeming (with)" , "surviving" , "Breathing, existing" , "Alert, active" , "Animated and kicking" .)
'active' is the definition.
(I've seen this before)
This is the entire clue.
(Other definitions for on the go that I've seen before include "Moving -- active" , "Busy and active" , "Active, in constant motion" , "Active and energetic" , "Keeping busy, not stopping" .)
'active' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for spry that I've seen before include "Sprightly" , "Fleet" , "Quick and agile" , "Agile (for one's age?)" , "Lively (especially of an older person)" .)
'active' is the definition.
(similar in meaning)
This is the entire clue.
(Other definitions for busy that I've seen before include "Pot plant" , "Sedulous" , "detective" , "crowded" , "Fully occupied" .)
'active' is the definition.
(associated in meaning)
This is the entire clue.
(Other definitions for lively that I've seen before include "Animated" , "Active" , "Con brio" , "Full of energy and high spirits" , "Full of zest or vigour" .)