Tails

v. remove the tail of an animal; furnish with a tail; come after, follow behind; gradually stop or disappear; follow a person in order to observe his activities

n. rear appendage on some animals; longer section at the back of an evening dress or jacket; detective who follows a person and keeps track of his activities; woman as a sex object (Derogatory Slang); buttocks, derriere (Slang)

The tail is the section at the rear end of an animal's body; in general, the term refers to a distinct, flexible appendage to the torso. It is the part of the body that corresponds roughly to the sacrum and coccyx in mammals and birds. While tails are primarily a feature of vertebrates, some invertebrates—including  scorpions and springtails—have tail-like appendages.
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Tail any slender appendage. tail of spermatozoon the flagellum of a spermatozoon, which contains the axonema; it has four regions: the neck, [more]Tails - Community and Resources

Noun
1. formalwear consisting of full evening dress for men
(synonym) dress suit, full dress, tailcoat, tail coat, white tie, white tie and tails
(hypernym) formalwear, eveningwear, evening dress, evening clothes
(part-meronym) swallow-tailed coat, swallowtail, morning coat

Noun
1. the posterior part of the body of a vertebrate especially when elongated and extending beyond the trunk or main part of the body
(hypernym) process, outgrowth, appendage
(hyponym) rattle
(part-holonym) vertebrate, craniate
(part-meronym) dock
(derivation) dock, bob
2. the time of the last part of something; "the fag end of this crisis-ridden century"; "the tail of the storm"
(synonym) fag end, tail end
(hypernym) end, ending
3. any projection that resembles the tail of an animal
(synonym) tail end
(hypernym) projection
4. the fleshy part of the human body that you sit on; "he deserves a good kick in the butt"; "are you going to sit on your fanny and do nothing?"
(synonym) buttocks, nates, arse, butt, backside, bum, buns, can, fundament, hindquarters, hind end, keister, posterior, prat, rear, rear end, rump, stern, seat, tail end, tooshie, tush, bottom, behind, derriere, fanny, ass
(hypernym) body part
(part-holonym) torso, trunk, body
5. a spy employed to follow someone and report their movements
(synonym) shadow, shadower
(hypernym) follower
(derivation) chase, chase after, trail, tag, give chase, dog, go after, track
6. (usually plural) the reverse side of a coin that does not bear the representation of a person's head
(antonym) head
(hypernym) reverse, verso
(part-holonym) coin
(classification) plural, plural form
7. the rear part of an aircraft
(synonym) tail assembly, empennage
(hypernym) rear, back
(part-holonym) fuselage
(part-meronym) horizontal tail
8. the rear part of a ship
(synonym) stern, after part, quarter, poop
(hypernym) rear, back
(part-holonym) ship
(part-meronym) escutcheon
Verb
1. go after with the intent to catch; "The policeman chased the mugger down the alley"; "the dog chased the rabbit"
(synonym) chase, chase after, trail, tag, give chase, dog, go after, track
(hypernym) pursue, follow
(hyponym) quest
(derivation) shadow, shadower
2. remove or shorten the tail of an animal
(synonym) dock, bob
(hypernym) cut
3. remove the stalk of fruits or berries
(hypernym) top, pinch

gou3 wei3 xu4 diao1
A dog's tail sequel a marten.
A wretched sequel to an excellent work.

wei4 shou3 wei4 wei3
Fearing the head and fearing the tail.
Referring to a person who is timid and overcautious and was full of misgivings before and after doing something.