Expedition as made by river in London? (8)
I believe the answer is:
alacrity
'expedition' is the definition.
(I've seen this before)
'as made by river in london?' is the wordplay.
'as' becomes 'a la' (French 'a la' - 'in the style of').
'made by' is a charade indicator (letters next to each other) (letters written or made by another set of letters).
'river' becomes 'r' (abbreviation).
'in' means one lot of letters goes inside another.
'london?' becomes 'city' (london is a kind of city).
'r' placed into 'city' is 'crity'.
'ala'+'crity'='ALACRITY'
(Other definitions for alacrity that I've seen before include "Quickness" , "Showing brisk readiness" , "Briskness, liveliness" , "Prompt and eager readiness" , "Enthusiasm; speed" .)