Fish gets meal without starting to turn round (5)
I believe the answer is:
tetra
'fish' is the definition.
(tetra is a kind of fish)
'meal without starting to turn round' is the wordplay.
'meal' becomes 'tea' (tea is a type of meal).
'without' means one lot of letters goes inside another ('without' can be similar in meaning to 'outside').
'starting to' indicates taking the first letters.
The first letters of 'turn round' is 'tr'.
'tea' enclosing 'tr' is 'TETRA'.
'gets' is the link.
(Other definitions for tetra that I've seen before include "Bright tropical fish" , "Brightly coloured aquarium fish" , "Small brightly-coloured fish of aquariums" , "This indicates a group of four" , "Swimmer" .)