<p><strong>Noun</strong></p><ul><li>a wall, wire screen, or the like, serving to prevent a ball from going too far beyond the normal playing area.</li><li>Baseball: the catcher.</li><li>a person or thing that serves as a support, safeguard, or reinforcement: There were technicians on board as backstops to the automated controls.</li></ul><p><strong>Verb</strong></p><ul><li>(used without object) back·stopped, back·stop·ping: to act as a backstop.</li><li>(used with object) back·stopped, back·stop·ping: to act as a backstop to: The government agreed to backstop companies that invested in oil exploration.</li></ul>