surer; surest
Definition of sure
(Entry 1 of 2)
1a : marked by or given to feelings of confident certainty
I'm sure I'm right
b : characterized by a lack of wavering or hesitation
sure brush strokes a sure hand
2 : admitting of no doubt : indisputable spoke from sure knowledge
b : bound to happen : inevitable sure disaster
4 : careful to remember, attend to, or find out something
be sure to lock the door
5 : firmly established : steadfast a sure hold
6 : reliable, trustworthy a sure friend
7 obsolete : safe from danger or harm
sure
adverbDefinition of sure (Entry 2 of 2)
: surely
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Keep scrolling for more
Test Your Vocabulary
Words of Snow and Ice Quiz
- Which of the following refers to thin, bending ice, or to the act of running over such ice?

Test your knowledge - and maybe learn something along the way.
TAKE THE QUIZ
Anagram puzzles meet word search.
TAKE THE QUIZLove words? Need even more definitions?
Merriam-Webster unabridgedWords at Play
Ask the Editors
Word Games
Words of Snow and Ice Quiz
A selection of words from the chillier parts of t...
Take the quizName that Thing: Toys and Games Edition
It's all fun and games until someone beats your h...
Take the quizTrue or False?
Test your knowledge - and maybe learn something a...
Take the quizSCRABBLE® Sprint
SCRABBLE® fans, sharpen your skills!
Play the game
Share sure
Time Traveler for sure
The first known use of sure was in the 13th century
See more words from the same century