Means to rescue European snake trapped by elevators (9)
I believe the answer is:
lifeboats
'means to rescue' is the definition.
'european snake trapped by elevators' is the wordplay.
'european' becomes 'e' (abbreviation e.g. EU).
'snake' becomes 'boa' (boa is a kind of snake).
'trapped by' indicates putting letters inside.
'elevators' becomes 'lifts' ('lift' can be a synonym of 'elevator').
'e'+'boa'='eboa'
'eboa' put inside 'lifts' is 'LIFEBOATS'.
(Other definitions for lifeboats that I've seen before include "Safety equipment" , "Vessels for rescue at sea" , "Crafts for rescue at sea" , "Craft for rescue at sea" , "They rescue people" .)