Intend a vessel to go round a little lake (4)
I believe the answer is:
plan
'intend' is the definition.
(planning is a kind of intending)
'a vessel to go round a little lake' is the wordplay.
'a vessel' becomes 'pan' (I have seen 'Shallow vessel ' mean 'pan' so perhaps 'vessel' could also mean 'pan'**).
'to go round' is an insertion indicator.
'a little' indicates taking the first letters.
The initial letter of 'lake' is 'l'.
'pan' enclosing 'l' is 'PLAN'.
(Other definitions for plan that I've seen before include "Map; intention" , "Scheme, design" , "Formulate" , "Scale drawing of a structure" , "Blueprint" .)