One who assumes.

plural of assumer

present participle of assume

haughty; arrogant

To authenticate by means of belief; to surmise; to suppose to be true, especially without proof / To take on a position, duty or form

An assumption.

simple past tense and past participle of assume

Used in a manner intended to deceive; pretended; simulated. / Supposed or presumed.

Capable of being assumed, or taken to be true. / Capable of being assumed, or taken on.

presumably; as one may assume