Coffee for reps ordered by oil company (8)
I believe the answer is:
espresso
'coffee' is the definition.
(espresso is a kind of coffee)
'reps ordered by oil company' is the wordplay.
'ordered' is an anagram indicator.
'by' says to put letters next to each other.
'oil company' becomes 'esso' (Esso is an oil company).
'reps' with letters rearranged gives 'espr'.
'espr'+'esso'='ESPRESSO'
'for' acts as a link.
(Other definitions for espresso that I've seen before include "Italian-style coffee" , "Seep Ross into the coffee" , "Kind of coffee made with steam" , "Coffee made by forcing steam through grounds" , "Italian strong coffee traditionally in a little cup" .)