In botany, a bulb is structurally a short stem with fleshy leaves or leaf bases that function as food storage organs during dormancy. (In gardening, plants with other kinds of storage organ are also called "ornamental bulbous plants" or just "bulbs".) 在植物学中，鳞茎在结构上是具有肉质叶或叶基的短茎，在休眠期间作为食物储存器官发挥作用。（在园艺中，带有其他贮藏器官的植物也被称为“观赏球茎植物”或“球茎植物”。）
Plants that form underground storage organs, including bulbs as well as tubers and corms, are called geophytes. 形成地下贮藏器官的植物，包括鳞茎、块茎和球茎，被称为地生植物。 Longitudinal section through an onion bulb:
In photography, bulb is named for the bulb on detachable rubber pneumatic shutter releases that came with early cameras. With shutters set to "B", the pneumatic release kept the shutter open for as long as the photographer squeezed the bulb—a "Bulb" exposure. Bulb是以早期相机附带的可拆卸橡胶气动快门释放装置上的灯泡命名的。当快门设置为“B”时，气动释放装置使快门保持打开状态，直到摄影师挤压bulb——一个“Bulb”曝光。[长得像血压计用的那种橡胶球，以形状命名。]
The use of flash powder in an open lamp was replaced by flashbulbs; magnesium filaments were contained in bulbs filled with oxygen gas, and electrically ignited by a contact in the camera shutter. 在开放式灯具中使用闪光粉被闪光灯取代；镁丝装在充满氧气的灯泡中，通过快门中的触点电点燃。
In technical usage, a replaceable component that produces light from electricity is called a lamp. Lamps are commonly called light bulbs; for example, the incandescent light bulb. 在技术用语中，一种可以从电中产生光的可更换组件被称为灯。灯通常被称为灯泡；例如，白炽灯泡。
A bulb keel is a keel, usually made with a high aspect ratio foil, that contains a ballast-filled bulb at the bottom, usually teardrop shaped. 球状龙骨是一种龙骨，通常由高宽高比箔片制成，底部有一个填充了压载物的球状物，通常为泪滴状。球鼻艏_百度百科
A foil is a solid object with a shape such that when placed in a moving fluid at a suitable angle of attack the lift (force generated perpendicular to the fluid flow) is substantially larger than the drag (force generated parallel to the fluid flow). If the fluid is a gas, the foil is called an airfoil or aerofoil, and if the fluid is water the foil is called a hydrofoil. 箔片是一种固体物体，其形状使得当以适当的迎角放置在移动的流体中时，升力（垂直于流体流动产生的力）远大于阻力（平行于流体流动产生的力）。如果流体是气体，则称为翼型，如果流体是水，则称为水翼。如何选择翼型 - 知乎
A foil generates lift primarily because of its shape and angle of attack. When oriented at a suitable angle, the foil deflects the oncoming fluid, resulting in a force on the foil in the direction opposite to the deflection. This force can be resolved into two components: lift and drag. 箔片产生升力主要是因为它的形状和攻角。当以合适的角度定向时，箔片会使迎面而来的流体偏转，从而在与偏转方向相反的方向上对箔片施加力。这个力可以分解为两个分量：升力和阻力。为啥飞机可以肚皮朝上飞(一小会)？
(击剑运动中的)钝头剑也叫foil.