Lose energy (8)
'lose energy' is the definition.
(I've seen this in another clue)
This is the entire clue.
(Other definitions for tire that I've seen before include "Feel in need of rest" , "Flag" , "Become exhausted" , "one of four found on Chevrolet?" , "Grow weary of rite" .)
(Other definitions for languish that I've seen before include "lose strength" , "Droop" , "Suffer hardship" , "Become discouraged" , "Wilt" .)