BOTTOM (4)

Bot″tom, v. i. 1. 1. To rest, as upon an ultimate support; to be based or grounded; — usually with on or upon.
Find on what foundation any proposition bottoms. Locke. 2. 2. To reach or impinge against the bottom, so as to impede free action, as when the point of a cog strikes the bottom of a space between two other cogs, or a piston the end of a cylinder.