Understatement

[ʌndə'steɪtm(ə)nt;'ʌndə-] or ['ʌndɚstetmənt]

Definition

(noun.) a statement that is restrained in ironic contrast to what might have been said.

Edited by Bridget--From WordNet

Definition

(n.) The act of understating, or the condition of being understated; that which is understated; a statement below the truth.

Typed by Leigh