Final spell in a lake (8)

I believe the answer is:

terminal

'final' is the definition.
(I know that final can be written as terminal)

'spell in a lake' is the wordplay.
'spell' becomes 'term' (term can mean a spell or period).
'lake' becomes 'L' (geographical abbreviation).
'term'+'in'+'a'+'l'='TERMINAL'

(Other definitions for terminal that I've seen before include "Passenger building" , "Last, final" , "Occurring at the end" , "Deathly" , "Final; connection point" .)

I've seen this clue in The Telegraph.

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