Artist sent up to top lawyer to fetch gelatinous substance made from seaweed (4)
I believe the answer is:
agar
'substance made from seaweed' is the definition.
(I've seen this in another clue)
'artist sent up to top lawyer' is the wordplay.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'sent up' is a reversal indicator.
'to' says to put letters next to each other (I've seen this in other clues).
'top lawyer' becomes 'AG' (abbreviation for attorney general).
'ra' back-to-front is 'ar'.
'ar' after 'ag' is 'AGAR'.
'to fetch gelatinous' is the link.
I am not very happy about this link. Some or all of it may be part of another bit of the clue.
Can you help me to learn more?
(Other definitions for agar that I've seen before include "found in the sea" , "Food-thickening jelly" , "Jelly used in bacteria culture" , "setter" , "a newspaper rejected" .)