from The American Heritage® Dictionary of the English Language, 4th Edition
- adv. With confidence; unhesitatingly.
- adv. Undoubtedly; certainly: You surely can't be serious.
- adv. Without fail: Slowly but surely spring returns.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adv. without fail.
- adv. certainly, undoubtedly.
- adv. with confidence.
from the GNU version of the Collaborative International Dictionary of English
- adv. In a sure or certain manner; certainly; infallibly; undoubtedly; assuredly.
- adv. Without danger; firmly; steadly; securely.
from The Century Dictionary and Cyclopedia
- Certainly; infallibly; undoubtedly; assuredly: often used, like doubtless, in a manner implying doubt or question.
- Firmly; stably; safely; securely.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adv. definitely or positively (`sure' is sometimes used informally for `surely')
sure + -ly (Wiktionary)