spontaneity

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. The quality or condition of being spontaneous.
2. n. Spontaneous behavior, impulse, or movement.

Century Dictionary and Cyclopedia

1. n. Spontaneous character or quality; that character of any action of any subject by virtue of which it takes place without being caused by anything distinguishable from the subject itself. Spontaneity does not imply the absence of a purpose or external end, but the absence of an external incitement or external efficient cause.
2. n. In biology, the fact of apparently automatic change in structure, or activity in function, of animals and plants, whereby new characters may be acquired, or certain actions performed, under no influence of external conditions or stimulus; animal or vegetable automatism. The inherent tendency of an individual organism to vary in structure without reference to its conditions of environment, as when a plant or animal sports; spontaneous variability. Some of the most valuable strains of domestic animals and cultivated plants have arisen thus spontaneously.

Wiktionary

1. n. uncountable The quality of being spontaneous.
2. n. countable Spontaneous behaviour.
3. n. biology The tendency to undergo change, characteristic of both animal and vegetable organisms, and not restrained or checked by the environment.
4. n. biology The tendency to activity of muscular tissue, including the voluntary muscles, when in a state of healthful vigour and refreshment.

GNU Webster's 1913

1. n. The quality or state of being spontaneous, or acting from native feeling, proneness, or temperament, without constraint or external force.
2. n. The tendency to undergo change, characteristic of both animal and vegetable organisms, and not restrained or checked by the environment.
3. n. The tendency to activity of muscular tissue, including the voluntary muscles, when in a state of healthful vigor and refreshment.

WordNet 3.0

1. n. the quality of being spontaneous and coming from natural feelings without constraint