Definitions

1. noun

A person who is more cunning or deceitful than another, especially in a clever or sneaky way

“He turned out to be the slier of the two, and managed to outwit his opponent.”

2. adjective

Clever or cunning in a way that is considered annoying or unpleasant

“Her slier tactics in the business deal eventually led to her success.”

3. adjective

More cunning or deceitful than another

“The slier of the two thieves managed to escape with the loot.”