This is the 8651st most frequent Japanese word.
断然
"断然" means "absolutely" or "decisively."
In this sentence, '断然' is used to strongly emphasize the superiority of the cafe's coffee, conveying that it is distinctly better than others.
このカフェのコーヒーは断然おいしいです。
The coffee at this cafe is by far the most delicious.
Here, '断然' serves to unequivocally endorse the individual as the best choice for the project leader role.
彼は断然プロジェクトのリーダーに適任だと思います。
I think he is absolutely the most suitable person as the leader of the project.
In this context, '断然' highlights the comparison of superiority in both price and quality regarding the manufacturer's products.