from The American Heritage® Dictionary of the English Language, 4th Edition
- adv. At once.
- adv. With insistence; urgently.
- conj. Chiefly British As soon as.
from the GNU version of the Collaborative International Dictionary of English
- adv. Without the least delay or interval; at once; immediately.
- adv. With urgency or importunity; earnestly; pressingly.
from The Century Dictionary and Cyclopedia
- At the same time; simultaneously.
- Immediately after; without any intervening time: as, to be instantly killed.
- With urgency; insistently; earnestly; assiduously.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adv. without any delay
- adv. without delay or hesitation; with no time intervening
From instant + -ly. (Wiktionary)