Strange oriental lake (5)
I believe the answer is:
eerie
'strange' is the definition.
(eerie means odd or strange)
'oriental lake' is the wordplay.
'oriental' becomes 'e'.
'lake' becomes 'erie' (Lake Erie is one of the Canadian/US 'Great Lakes').
'e'+'erie'='EERIE'
(Other definitions for eerie that I've seen before include "Spooky, creepy" , "Sinister" , "Strange, unusual" , "Spooky, weird" , "Spectral" .)