(uncountable) The state or characteristic of being reasonable. / (countable) A reasonable action or behaviour.

plural of reasonableness

That which causes something: an efficient cause, a proximate cause. / A motive for an action or a determination.

(intransitive) To deduce or come to a conclusion by being rational / (intransitive) To perform a process of deduction or of induction, in order to convince or to confute; to argue.

(now rare) Having the faculty of reason; rational, reasoning. / Just; fair; agreeable to reason. / Not excessive or immoderate; within due limits; proper. / Not expensive; fairly priced. / Satisfactory.

plural of reasoner

One who reasons.

plural of reasoning

present participle of reason

The deduction of inferences or interpretations from premises; abstract thought; ratiocination. / A Rastafari meeting held for the purposes of chanting, prayer and discussion.