der Wichtigste
Translation
the most important one (male), the most important thing
Examples
Er ist der Wichtigste im Team.
He is the most important one on the team.
Das Wichtigste ist die Gesundheit.
The most important thing is health.
Grammar Patterns
((as a noun)) used as a noun The most important thing is that you are happy.
Similar Words
die Hauptsache (the main thing), die Priorität (priority); Antonym: der Unwichtigste (the least important one)
Etymology
This is the nominalized superlative form of the adjective 'wichtig' (important). The '-st-' marks the superlative.
Memory Tips
Remember that adjectives can become nouns in German. 'wichtig' + superlative '-st-' + ending '-er' = 'the most important one'.