What is "rat snake"

Rat \Rat\ (r[a^]t), n. [AS. r[ae]t; akin to D. rat, OHG. rato, ratta, G. ratte, ratze, OLG. ratta, LG. & Dan. rotte, Sw. r[*a]tta, F. rat, Ir. & Gael radan, Armor. raz, of unknown origin. Cf. Raccoon.]

1. (Zo["o]l.) One of several species of small rodents of the genus Rattus (formerly included in Mus) and allied genera, of the family Muridae, distinguished from mice primarily by being larger. They infest houses, stores, and ships, especially the Norway rat, also called brown rat, ( Rattus norvegicus formerly Mus decumanus), the black rat ( Rattus rattus formerly Mus rattus), and the roof rat (formerly Mus Alexandrinus, now included in Rattus rattus). These were introduced into America from the Old World. The white rat used most commonly in laboratories is primarily a strain derived from Rattus rattus.

2. A round and tapering mass of hair, or similar material, used by women to support the puffs and rolls of their natural hair. [Local, U.S.]

3. One who deserts his party or associates; hence, in the trades, one who works for lower wages than those prescribed by a trades union. [Cant] Note: ``It so chanced that, not long after the accession of the house of Hanover, some of the brown, that is the German or Norway, rats, were first brought over to this country (in some timber as is said); and being much stronger than the black, or, till then, the common, rats, they in many places quite extirpated the latter. The word (both the noun and the verb to rat) was first, as we have seen, leveled at the converts to the government of George the First, but has by degrees obtained a wider meaning, and come to be applied to any sudden and mercenary change in politics.'' --Lord Mahon. Bamboo rat (Zo["o]l.), any Indian rodent of the genus Rhizomys. Beaver rat, Coast rat. (Zo["o]l.) See under Beaver and Coast. Blind rat (Zo["o]l.), the mole rat. Cotton rat (Zo["o]l.), a long-haired rat ( Sigmodon hispidus), native of the Southern United States and Mexico. It makes its nest of cotton and is often injurious to the crop. Ground rat. See Ground Pig, under Ground. Hedgehog rat. See under Hedgehog. Kangaroo rat (Zo["o]l.), the potoroo. Norway rat (Zo["o]l.), the common brown rat. See Rat. Pouched rat. (Zo["o]l.)

   1. See Pocket Gopher, under Pocket.

   2. Any African rodent of the genus Cricetomys.

      Rat Indians (Ethnol.), a tribe of Indians dwelling near Fort Ukon, Alaska. They belong to the Athabascan stock.

      Rat mole. (Zo["o]l.) See Mole rat, under Mole.

      Rat pit, an inclosed space into which rats are put to be killed by a dog for sport.

      Rat snake (Zo["o]l.), a large colubrine snake ( Ptyas mucosus) very common in India and Ceylon. It enters dwellings, and destroys rats, chickens, etc.

      Spiny rat (Zo["o]l.), any South American rodent of the genus Echinomys.

      To smell a rat. See under Smell.

      Wood rat (Zo["o]l.), any American rat of the genus Neotoma, especially Neotoma Floridana, common in the Southern United States. Its feet and belly are white.

n. any of various nonvenomous rodent-eating snakes of North America and Asia

Rat snakes (or ratsnakes) are members – along with kingsnakes, milk snakes, vine snakes and indigo snakes – of the subfamily Colubrinae of the family Colubridae. They are medium to large constrictors and are found throughout much of the Northern Hemisphere. They feed primarily on rodents and birds. With some species exceeding 3 m (10 ft) in total length, they can occupy top levels of some food chains. Many species make attractive and docile pets and one, the corn snake, is one of the most popular reptile pets in the world. Other species can be very skittish and sometimes aggressive, but bites are rarely serious. Like nearly all colubrids, rat snakes pose no threat to humans. Rat snakes were long thought to be completely nonvenomous, but recent studies have shown that some Old World species do possess small amounts of venom (so small as to be negligible to humans).

Previously, most rat snakes were assigned to the genus Elaphe, but many have been since renamed following mitochondrial DNA analysis performed in 2002. For the purpose of this article, names will be harmonized with the TIGR Database.