Fire up learner admitted by helpful European (6)
I believe the answer is:
kindle
'fire up' is the definition.
(thesaurus)
'learner admitted by helpful european' is the wordplay.
'learner' becomes 'l'.
'admitted by' means one lot of letters goes inside another.
'helpful' becomes 'kind' ('kind' can be similar in meaning to 'helpful').
'european' becomes 'e' (abbreviation e.g. EU).
'kind'+'e'='kinde'
'l' going within 'kinde' is 'KINDLE'.
(Other definitions for kindle that I've seen before include "Ignite" , "reading facilitated by this?" , "Light (fire)" , "Inflame" , "Exclamation, shout" .)