This is the 15211th most frequent German word.
treuesten
"Most loyal."
The word 'treuesten' is used as a superlative adjective describing the loyalty of the friends.
Er ist einer meiner treuesten Freunde.
He is one of my most loyal friends.
'Treuesten' functions as a superlative demarcating the highest level of loyalty among supporters.
Meine treuesten Anhänger unterstützen mich in jeder Situation.
My most loyal supporters stand by me in every situation.
Here, 'treuesten' modifies 'Versprechen' (promise), emphasizing its supreme level of fidelity.