assumption-n; 4 Senses

Sense Number 1: a statement or a hypothesis that is assumed to be true, and from which a conclusion can be drawn; or the act of assuming or taking for granted.

Commentary:ASSUMPTION [+event][+act_of_assuming][+thing_assumed]

Your assumption that I would agree was unwarranted.
On the assumption that he has been injured, we inferred that he will not play.
Any society is built upon certain assumptions.

WordNet 3.0 Sense Numbers: 1, 2

Sense Number 2: laying claim, the act of taking possession of, or power over, something.

Commentary:ASSUMPTION [+event][+possessing_by_force][+thing_possessed]

His assumption of office coincided with the trouble in Cuba.
The Nazi assumption of power in 1934.
He acquired all the company's assets for ten million dollars, and with them, the assumption of the company's debts.

WordNet 3.0 Sense Numbers: 3

Sense Number 3: Referring either to the Assumption of St. Mary, August 15, the celebration in the Roman Catholic Church of the Virgin Mary's being taken up into heaven when her earthly life had ended, or the act of this ascension of The Virgin Mary.

Commentary:ASCENSION [+act_of_arriving_in_heaven_in_bodily_form][+commemeoration_of_the_ascension_of_The_Virgin_Mary][+recurring_yearly_event]

We attend the street festival held at Mt. Carmel every year during Ascension.
since the 4th Century AD, Catholic and Orthodox churches have celebrated the Ascension of St. Mary on August the 15th.
St Mary's assumption is proven by the fact that no one has her body, and we'd have it if she had not been assumed.

WordNet 3.0 Sense Numbers: 4, 5

Sense Number 4: presumption, presumptuousness, effrontery, audacious (even arrogant) behavior that one has no right to exhibit

Commentary:ASSUMPTION [+event][+presumptuous_person][+thing_wrongly_assumed][+arrogance]

He hated his relatives for their assumption of imposing themselves upon his good-nature and large house.
your assumption that the splenda is for everyone in the office is wrong-headed and arrogant.
who are you to make this sort of assumption???

WordNet 3.0 Sense Numbers: 6