from The American Heritage® Dictionary of the English Language, 4th Edition
- adj. Happening or arising without apparent external cause; self-generated.
- adj. Arising from a natural inclination or impulse and not from external incitement or constraint.
- adj. Unconstrained and unstudied in manner or behavior.
- adj. Growing without cultivation or human labor.
from Wiktionary, Creative Commons Attribution/Share-Alike License
- adj. Self generated; happening without any apparent external cause.
- adj. Done by one's own free choice, or without planning.
- adj. proceeding from natural feeling or native tendency without external constraint
- adj. arising from a momentary impulse
- adj. controlled and directed internally : self-active : spontaneous movement characteristic of living things
- adj. produced without being planted or without human labor : indigenous
- adj. not apparently contrived or manipulated : natural
- adj. Random.
- adj. Sudden, without warning.
from the GNU version of the Collaborative International Dictionary of English
- adj. Proceeding from natural feeling, temperament, or disposition, or from a native internal proneness, readiness, or tendency, without constraint.
- adj. Proceeding from, or acting by, internal impulse, energy, or natural law, without external force
- adj. Produced without being planted, or without human labor.
from The Century Dictionary and Cyclopedia
- Proceeding from a conscious or unconscious internal impulse; occurring or done without the intervention of external causes; in a restricted sense, springing from one's own desire or volition, apart from any external suggestion or incitement.
- Growing naturally, without previous human care.
- Growing as native; indigenous.
- In biology, instinctive or automatic, as some actions of animals which depend upon no external stimulus and are performed without apparent motive or purpose; uninfluenced by external conditions, as a change in structural character. Compare spontaneity, 2.
- Synonyms Willing, etc. (see voluntary), instinctive, unbidden.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- adj. said or done without having been planned or written in advance
- adj. happening or arising without apparent external cause
From Late Latin spontāneus, of one's own accord, from Latin sponte.(American Heritage® Dictionary of the English Language, Fourth Edition)
Late Latin spontaneus, from Latin sponte (sua) ("of one's free will, voluntarily"). (Wiktionary)