noun (1), often attributive
\ ˈtāl How to pronounce tail (audio) \

Definition of tail

 (Entry 1 of 4)

1 : the rear end or a process or prolongation of the rear end of the body of an animal
2 : something resembling an animal's tail in shape or position: such as
a : a luminous stream of particles, gases, or ions extending from a comet especially in the antisolar direction
b : the rear part of an airplane consisting usually of horizontal and vertical stabilizing surfaces with attached control surfaces
3 : the reverse of a coin usually used in pluraltails, I win
4 tails plural
b : full evening dress for men
5 : a location immediately or not far behind had a posse on his tail
6 : one (such as a detective) who follows or keeps watch on someone
b slang, vulgar : sexual intercourse
9 : the back, last, lower, or inferior part of something
10 : tailing sense 1 usually used in plural
11 : the blank space at the bottom of a page


tailed; tailing; tails

Definition of tail (Entry 2 of 4)

transitive verb

1 : to follow for purposes of surveillance
2 : to connect end to end
3a : to remove the tail of (an animal) : dock entry 3
b : to remove the stem or bottom part of topping and tailing gooseberries
4a : to make or furnish with a tail
b : to follow or be drawn behind like a tail

intransitive verb

1 : to form or move in a straggling line
2 : to grow progressively smaller, fainter, or more scattered : abate usually used with offproductivity is tailing off— Tom Nicholson
3 : to swing or lie with the stern in a named direction used of a ship at anchor

Definition of tail (Entry 3 of 4)

Definition of tail (Entry 4 of 4)

: limited as to tenure : entailed

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Other Words from tail

Noun (1)

tailed \ ˈtāld How to pronounce tailed (audio) \ adjective
tailless \ ˈtāl-​ləs How to pronounce tailless (audio) \ adjective
taillike \ ˈtāl-​ˌlīk How to pronounce taillike (audio) \ adjective


tailer noun

Synonyms & Antonyms for tail

Synonyms: Verb

Antonyms: Verb

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Examples of tail in a Sentence

Verb The police had been tailing the suspect for several miles. She is constantly tailed by the press. The pitch tailed away from the batter.
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First Known Use of tail

Noun (1)

before the 12th century, in the meaning defined at sense 1


1523, in the meaning defined at transitive sense 2

Noun (2)

14th century, in the meaning defined above


15th century, in the meaning defined above

History and Etymology for tail

Noun (1)

Middle English, from Old English tægel; akin to Old High German zagal tail, Middle Irish dúal lock of hair

Noun (2)

Middle English, from Anglo-French, from tailler


Middle English taille, from Anglo-French taylé, past participle of tailler to cut, limit — more at tailor

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Time Traveler for tail

Time Traveler

The first known use of tail was before the 12th century

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Statistics for tail

Cite this Entry

“Tail.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/tail. Accessed 23 Oct. 2020.

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More Definitions for tail



English Language Learners Definition of tail

informal : to follow (someone) closely
: to move in a line that is not straight


\ ˈtāl How to pronounce tail (audio) \

Kids Definition of tail

 (Entry 1 of 2)

1 : the rear part of an animal or a usually slender flexible growth that extends from this part
2 : something that in shape, appearance, or position is like an animal's tail the tail of a coat
3 : the back, last, or lower part of something the tail of an airplane
4 : the side or end opposite the head

Other Words from tail

tailed \ ˈtāld \ adjective
tailless \ ˈtāl-​ləs \ adjective


tailed; tailing

Kids Definition of tail (Entry 2 of 2)

: to follow closely to keep watch on Police tailed the suspect.


noun, often attributive
\ ˈtā(ə)l How to pronounce tail (audio) \

Medical Definition of tail

1 : the rear end or a process or prolongation of the rear end of the body of an animal
2 : one end of a molecule regarded as opposite to the head especially : the end of a lipid molecule that consists of a nonpolar hydrocarbon chain and is opposite to the polar group most surface-active agents have a long hydrophobic tail attached to a polar head — R. E. Kirk & D. F. Othmer
3 : any of various parts of bodily structures that are terminal: as
a : the distal tendon of a muscle
b : the slender left end of the human pancreas
c : the common convoluted tube that forms the lower part of the epididymis
4 : the motile part of a sperm that extends from the middle piece to the end and comprises the flagellum
5 : a thin protein tube which forms part of the coat of some bacteriophages and through which DNA is injected into a cell

Other Words from tail

tailed \ ˈtā(ə)ld How to pronounce tailed (audio) \ adjective
tailless \ ˈtā(ə)l-​les How to pronounce tailless (audio) \ adjective

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Legal Definition of tail

 (Entry 1 of 2)

1 : the condition of being limited or restricted by entailing a tenant in tail

Legal Definition of tail (Entry 2 of 2)

: limited as to tenure — see also fee tail at fee sense 1

History and Etymology for tail


Anglo-French, literally, cutting, from Old French, from taillier to cut, prune

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