Formed of units mostly produced from a mould – right? (7)
I believe the answer is:
modular
'formed of units mostly' is the definition.
I can't judge whether this definition defines the answer.
'from a mould right?' is the wordplay.
'from' indicates an anagram (from the letters).
'right?' becomes 'r' (common abbreviation).
'a'+'mould'='amould'
'amould' with letters rearranged gives 'modula'.
'modula'+'r'='MODULAR'
'produced' is the link.
Can you help me to learn more?
(Other definitions for modular that I've seen before include "Made from detachable pieces" , "Built from separate units" , "in several parts" , "Made of units" .)