He means to make hay while the sun shines (3)
I believe the answer is:
ted
'he' is the definition.
'to make hay while the sun shines' is the wordplay.
I cannot quite understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
The remaining letters 'ed' is a valid word which might be clued in a way I don't understand.
This explanation may well be incorrect...
'means' acts as a link.
Can you help me to learn more?
(Other definitions for ted that I've seen before include "Edward, in short" , "The familiar American Senator Kennedy" , "- Hughes, Eng. Poet" , "Father ..., Dermot Morgan's TV creation" , "one of the Kennedys" .)