彗翎是天文学上用来描述彗星三种指向不同方向彗尾的名词之一，是彗星在经过太阳附近时出现的一种现象。彗翎是从彗发出发，指向太阳方向的彗尾，也称为反尾，这是因为几何关系而不同于其他的彗尾：离子尾和尘埃尾。彗翎是由颗粒较大的尘埃粒子形成的，它几乎不受太阳风和辐射压的影响，并且往往形成碟状留在彗星的轨道平面上。当地球经过彗星的轨道平面时，可以从侧面看见这个碟型物，并且呈现细长的形状。有时可以从另一个方向上看见，但经常会沉浸在尘埃尾当中。因此，只有在地球通过彗星轨道平面的短暂时间内，可以看见彗翎的出现。

多数的彗星未能充分的发展出可以被看见的彗翎，但是包括1957年的阿兰德-罗兰彗星和1997年的海尔·波普彗星，都曾有值得注意且明显的彗翎。

An antitail is a spike projecting from a comet's coma which seems to go towards the Sun, and thus geometrically opposite to the other tails: the ion tail and the dust tail. However, this phenomenon is an optical illusion that is seen from the Earth. The antitail is formed of larger dust particles, which are less affected by the Sun's radiation pressure and tend to remain roughly in the comet's orbital plane and eventually form a disc along the comet's orbit due to the ejection speed of the particles from the comet's surface. As Earth passes through the comet's orbital plane, this disc is seen side on, and appears as the characteristic spike. The other side of the disc can sometimes be seen, though it tends to be lost in the dust tail. The antitail is therefore normally visible for a brief interval only when Earth passes through the comet's orbital plane.