New loader on trial (6)
I believe the answer is:
ordeal
'trial' is the definition.
(thesaurus)
'new loader' is the wordplay.
'new' indicates an anagram.
'loader' anagrammed gives 'ORDEAL'.
'on' acts as a link.
(Other definitions for ordeal that I've seen before include "Tribulation" , "A test of endurance or or difficult experience" , "A difficult or harrowing time" , "Prolonged distressing experience" , "Ancient form of trial" .)