drawbridge
A bridge that can be raised or drawn up, typically over a moat or waterway.
A drawbridge spans the castle entrance.
bascule bridge
A type of drawbridge with a counterweighted leaf that rises; a more technical term.
This drawbridge is a type of bascule bridge.
Standard kanji spelling for a drawbridge or bascule bridge.
Mixed kanji-kana spelling, also common.
Compound of 跳ね (hane, 'springing up', from 跳ねる haneru) + 橋 (hashi, 'bridge'). The hashi changes to bashi due to rendaku.