unmistakably

Unmistakably means so clearly that it could not be taken for anything else. There is no second possibility.

It usually sits before an adjective or a noun phrase, giving unmistakably British, unmistakably his handwriting, unmistakably the smell of burning. The word does emphasis rather than description, since it insists on certainty. It is often spelled unmistakeably with an e, and both are accepted. Clearly and obviously do the same job with less force behind them.