Flatten :: Flatten (a.) To reduce to an even surface or one approaching evenness; to make flat; to level; to make plane.
Flatten :: Flatten (a.) To throw down; to bring to the ground; to prostrate; hence, to depress; to deject; to dispirit..
Flatten :: Flatten (a.) To make vapid or insipid; to render stale.
Flatten :: Flatten (a.) To lower the pitch of; to cause to sound less sharp; to let fall from the pitch.
Flatten :: Flatten (v. i.) To become or grow flat, even, depressed dull, vapid, spiritless, or depressed below pitch..