A powerful unit raised on the 1st of October, in Canada (6)
I believe the answer is:
ottawa
'in canada' is the definition.
(I know that Ottawa is part of Canada)
'a powerful unit raised on the 1st of october' is the wordplay.
'powerful unit' becomes 'watt' (watt is a kind of unit. I am not sure about the 'powerful' bit.).
'raised' shows that the letters should be reversed in order (going up in a down clue).
'on' says to put letters next to each other.
'the wst of october' becomes 'o' (wst letter of 'october').
'a'+'watt'='awatt'
'awatt' written backwards gives 'ttawa'.
'ttawa' put after 'o' is 'OTTAWA'.
Can you help me to learn more?
(Other definitions for ottawa that I've seen before include "North American city" , "The capital of Canada (6)" , "Canadian city" , "Canadian capital" , "Foreign capital" .)