Of actions, feelings: Unpremeditated, done without forethought. Obsolete or archaic.

= unpremeditated, adj.

Done, said, or conceived on the spur of the moment; not premeditated or studied beforehand; impromptu; off-hand.

Having no purpose; (also) not intentional, not done or happening on purpose.

Not meditated. Earliest in unmeditated upon.

= extemporal, adj.

Not premeditated; unplanned, spontaneous.

Not plotted; (in early use) spec. unplanned.

Unpremeditated; esp. of prayer, discourse, composition, etc.; = extempore, adv. 2. Occasionally of a speaker; †formerly also of the ability to speak.

= extemporaneous, adj.

= extempore, v.

Unpremeditated.

Unpremeditated. Obsolete.

Not entrenched. Obsolete. rare.

Done or produced extempore.

Not thought of; unexpected; unpremeditated.

Not projected (in various senses).

Of actions: Done without deliberation or forethought; not carefully considered or planned beforehand. Also of thoughts, words, etc…

Not premeditated or studied, off-hand, extempore; esp. of discourse, prayer, etc. Rarely of a person: Speaking extempore; also, inclined to…

= indeliberate, adj. 2.

= autoschediastic, adj. (Sometimes in humorous use.)

Occurring or brought about without design or premeditation; coming up or presenting itself ‘as it chances’.

Of action, speech, etc.: unpremeditated, extemporaneous, impromptu; (also) having the air or style of something so done; free and easy, unstudied…

(un-, prefix1 affix 2.)

= extemporaneous, adj.

Not planned; esp. not organized or anticipated; unconsidered, spontaneous.

Composed or uttered without preparation or premeditation; improvised; invented, produced, etc. on the spur of the moment and without previous thought.

on (also upon) the spur of the moment (or occasion,etc.), without premeditation or deliberation; on a momentary impulse; impromptu, suddenly…

Written, composed, etc., on the spur of the moment; extemporized, hastily improvised.

= C. 1.

Invented, created, or done spontaneously or on the spur of the moment, esp. as a result of necessity; impromptu.

in senses of the verb.

Of utterances, etc.: Coming freely and without premeditation or effort.

Unaccompanied by, not done with, consideration or intention.

Not planned or intended.

improvised.

Improvised, extemporaneous; unscripted.

Unplanned, haphazard, random.

Colloquial phrases: off the cuff (as if from notes made on the shirt-cuff) originally U.S., extempore, on the spur of the moment, unrehearsed; also…