Lethargy shown by overweight Miguel taking clothes off (7)
I believe the answer is:
fatigue
'lethargy' is the definition.
(I know that lethargy can be written as fatigue)
'by overweight miguel taking clothes off' is the wordplay.
'by' means one lot of letters go next to another.
'overweight' becomes 'fat' (similar in meaning).
'taking clothes off' means to look at the middle letters (remove the external letters which clothe the word).
The middle letters of 'miguel' are 'igue'.
'fat'+'igue' is 'FATIGUE'.
'shown' is the link.
(Other definitions for fatigue that I've seen before include "Chronic symptom" , "military chore" , "Weariness, exhaustion" , "Tiredness after effort" , "Weariness, state of tiredness" .)