toughest
adj.adj. the most difficult, strong, or determined. You use this to describe the person or thing that can handle the most pressure or pain.
adj. the superlative form of 'tough', indicating the highest degree of physical or mental resilience, difficulty, or durability.
This is the toughest exam I have ever taken.
The manager had to make the toughest decision of her career when she closed the branch.
While the marathon is physically demanding, the toughest part for most runners is the psychological battle that begins after the twentieth mile.
Superlative form of 'tough'; typically preceded by the definite article 'the'.
the most toughestthe toughestSince 'tough' is a one-syllable adjective, the superlative is formed by adding '-est', not by using 'most'.