highest
adj.adj. at the top level or position compared to everything else. You use this to describe the most extreme point of height, rank, or amount.
adj. the superlative form of high, indicating the maximum degree of vertical extent, rank, or intensity.
Mount Everest is the highest mountain in the world.
The company reported its highest profits in a decade after expanding into international markets.
The committee awarded the contract to the firm that demonstrated the highest level of technical expertise while maintaining a sustainable budget for the duration of the project.
As a superlative adjective, it is almost always preceded by the definite article 'the'.
the most highestthe highestSuperlative adjectives ending in '-est' do not take 'most'; this is a double superlative error.