Precisely, deformation of точно. Used as an enthusiastic expression of agreement, confirmation, or sudden realisation.
Точняк, он бы чётко объяснил, чем кавказ отличается от Альп :)
Spot on, he should explain clearly in which way the Caucasus is different from the Alps :)
(petro @ kiteforum.spb.ru, 12/2010)
