Fruit gives a chap energy (5)
I believe the answer is:
mango
'fruit' is the definition.
(type of fruit)
'a chap energy' is the wordplay.
'a chap' becomes 'man' (chap can mean a man).
'energy' becomes 'go' (go can mean energy or enthusiasm).
'man'+'go'='MANGO'
'gives' acts as a link.
(Other definitions for mango that I've seen before include "No, Mag has the odd fruit" , "product" , "Ovoid edible fruit" , "Yellow-fleshed fruit" , "Tropical fruit, its pickle" .)