Extremist on hand beginning to energise throng (5)

I believe the answer is:

horde

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'throng' is the definition.
(horde is a kind of throng)

'extremist on hand beginning to energise' is the wordplay.
'extremist' becomes 'hod' (I am not sure about this - if you are sure you should believe this answer much more).
'on' indicates putting letters inside (as in clothing 'on' a person).
'hand' becomes 'R' (abbreviation for right, as in the right-hand side).
'beginning to' suggests taking the first letters.
The initial letter of 'energise' is 'e'.
'hod' placed around 'r' is 'hord'.
'hord'+'e'='HORDE'

Can you help me to learn more?

(Other definitions for horde that I've seen before include "A moving crowd" , "Nomadic army" , "Vast crowd" , "Huge noisy crowd" , "A swarm or multitude" .)

I've seen this clue in The Independent.

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