Tail1  —n. 1 hindmost part of an animal, esp. Extending beyond the body. 2 a thing like a tail, esp. An extension at the rear. B rear of a procession etc. 3 rear part of an aeroplane, vehicle, or rocket. 4 luminous trail following a comet. 5 inferior, weaker, or last part of anything. 6 part of a shirt or coat below the waist at the back. 7 (in pl.) Colloq. A tailcoat. B evening dress including this. 8 (in pl.) Reverse of a coin as a choice when tossing. 9 colloq. Person following another. —v. 1 remove the stalks of (fruit). 2 (often foll. By after) colloq. Follow closely.  on a person's tail closely following a person. Tail off (or away) gradually decrease or diminish; end inconclusively. With one's tail between one's legs dejected, humiliated.  tailless adj. [old english]