certainly — English Dictionary

Adverb

1. In a way which is certain; with certainty.

   Examples

   More examples (1)

   he verily thought he had young live frogs in his belly, qui vivebant ex alimento suo, that lived by his nourishment, and was so certainly persuaded of it, that for many years following he could not be rectified in his conceit.

   The torque was "built up" in the special back axle and the car crawled tankwise but very certainly over the obstacles without a jar or hesitation.

2. Without doubt, surely.

   Examples

   The accident was certainly caused by human error.

   That was certainly sweet of him.

   More examples (3)

   'I'm all grown up now' -'You certainly have (grown)!'

   So this was my future home, I thought! Certainly it made a brave picture. I had seen similar ones fired-in on many a Heidelberg stein. Backed by towering hills,[…]a sky of palest Gobelin flecked with fat, fleecy little clouds, it in truth looked a dear little city; the city of one's dreams.

   WikiLeaks did not cause these uprisings but it certainly informed them. The dispatches revealed details of corruption and kleptocracy that many Tunisians suspected, but could not prove, and would cite as they took to the streets.

3. An emphatic affirmative answer; of course.

   Examples

   Would you like it with ice? Certainly, and with lemon please.

Adverb

1. definitely or positively (‘sure’ is sometimes used informally for ‘surely’)

   Synonyms

   surelysurefor surefor certainsure enoughsure as shooting

   Examples

   the results are surely encouraging

   she certainly is a hard worker

   More examples (6)

   it's going to be a good day for sure

   they are coming, for certain

   they thought he had been killed sure enough

   he'll win sure as shooting

   they sure smell good

   sure he'll come