(1):

(n.) A valuation of property or profits of business, for the purpose of taxation; such valuation and an adjudging of the proper sum to be levied on the property; as, an assessment of property or an assessment on property.

(2):

(n.) The specific sum levied or assessed.

(3):

(n.) An apportionment of a subscription for stock into successive installments; also, one of these installments (in England termed a "call").

(4):

(n.) The act of assessing; the act of determining an amount to be paid; as, an assessment of damages, or of taxes; an assessment of the members of a club.