Unstable lab set used by the mathematicians (6)
I believe the answer is:
tables
'the mathematicians' is the definition.
Although both the answer and definition are plural nouns, I can't understand how one could define the other.
'unstable lab set' is the wordplay.
'unstable' is an anagram indicator.
'lab'+'set'='labset'
'labset' anagrammed gives 'TABLES'.
'used by' is the link.
Can you help me to learn more?
(Other definitions for tables that I've seen before include "Lists of figures arranged in columns" , "Flat-topped pieces of furniture (which can be turned?)" , "Turn these to gain the upper hand" , "Turn these to reverse the odds" , "Sit at the strange stable" .)