This is the 4551st most frequent German word.
reiner
"Reiner" in German means "purer" or "cleaner," often used as a comparative form of "rein" (pure).
In this sentence, 'reiner' is used as an adjective to describe 'Unsinn' (nonsense), meaning 'pure' or 'sheer', indicating the completeness or total nature of the nonsense.
Das ist reiner Unsinn.
That is pure nonsense.
Here, 'reiner' modifies 'Anfänger' (beginner) to mean 'pure', referring to someone who is completely new to the subject or activity, emphasizing their novice status.
Er ist ein reiner Anfänger.
He is a pure beginner.
In this comparative sentence, 'reiner' is used as the comparative form of 'rein' (pure), indicating a higher degree of purity for the air in the mountains compared to the city.