Great initial measures. Good ones (4)
I believe the answer is:
gems
'good ones' is the definition.
Although both the answer and definition are plural nouns, I cannot understand how one could define the other.
'great initial measures' is the wordplay.
'initial' indicates taking the first letters.
'measures' becomes 'ems' (en is a unit of measurement used by printers).
The initial letter of 'great' is 'g'.
'g'+'ems'='GEMS'
Can you help me to learn more?
(Other definitions for gems that I've seen before include "Precious stones" , "Valuable stones" , "Jewels" .)