The French experiment is current (6)
I believe the answer is:
latest
'is current' is the definition.
(similar in meaning)
'the french experiment' is the wordplay.
'the french' becomes 'la' (one of the French words for 'the').
'experiment' becomes 'test' (test is a kind of experiment).
'la'+'test'='LATEST'
(Other definitions for latest that I've seen before include "style of today" , "Most recent, hot off the press" , "Most recent or tardiest" , "hot bit of news" , "delayed more than all others" .)