<p><strong>Noun:</strong></p><ul><li>Nautical: the clear space between two decks.</li><li>Also called headway.</li><li>Clear vertical space, as between the head and sill of a doorway, the ceiling and floor of a room, or the ceiling of a vehicular passageway and a vehicle roof, as to allow passage or comfortable occupancy: over 7.5 feet of headroom in the attic; a covered bridge with limited headroom.</li><li>Clear vertical space above one’s head, as in a vehicle or room: plenty of headroom for passengers.</li><li>Audio: dynamic headroom.</li></ul><p><strong>Verb (used with object):</strong></p><ul><li>Fet·tled, fet·tling.</li><li>Ceramics: to remove mold marks from (a cast piece).</li><li>Metallurgy: to remove sand from (a casting).</li><li>To repair the hearth of (an open-hearth furnace).</li></ul>