The unclued lights (one of two words), individually or as three pairs, are of a kind.
 

Across

 
9    Aussie’s error with fine paintbrush. Correct! (10, hyphened)
11    Ten-nil reverse. That’s rare (5)
12    Publicly accuse having arrived in Georgia, drunk (7)
14    Zest for two-thirds of the month before October 1st (5)
15    Savings account on account for Sarah’s son (5)
22    Suffer county’s disappointment (7, hyphened)
23    River’s quiet and very still (4)
27    In France Tom’s by water in Bordeaux vineyard (7)
28    Treading around incline (8)
33    Disorderly students’ horseplay with wrestling team (6)
34    Sound asleep (5)
37    Belch going to gaol, charged with drink (7, two words)
38    Cheerless day...