# tails

/ˈteɪɫz/ (US) · /tˈeɪlz/ (UK)

Source: https://englishreference.com/word/tails
Updated: 2026-06-20

## Senses

### 1. plural of tail

noun · CEFR A2

the long parts at the back of animals' bodies.

For teachers: the plural form of the posterior appendage of an animal.

- The two dogs wagged their tails happily when their owner came home.
- The biologist noted that the various species of lemurs used their long tails for balance while navigating the thin branches of the canopy.

### 2. side of a coin

noun · CEFR B1

the side of a coin that does not have a person's face on it.

For teachers: the reverse side of a coin, opposite the obverse or 'heads' side.

- He flipped the coin and it landed on tails, so I had to go first.
- In many sports, a referee flips a coin and asks the captains to choose heads or tails to determine which team kicks off first.

### 3. formal clothing

noun · CEFR B2 · Formal

a very formal black jacket that is short in the front and long in the back.

For teachers: a man's formal evening suit featuring a coat with a divided skirt at the back; a clipping of 'tailcoat'.

- The musicians in the orchestra all wore black tails for the gala performance.
- The invitation specified white tie, requiring the gentlemen to arrive in full tails and a stiff-fronted shirt.

### 4. industrial waste

noun · CEFR C2 · Technical

the waste material left over after processing ore or making alcohol.

For teachers: the residue or waste remaining after the valuable part of an ore has been extracted; also used for the final part of a liquid distillation.

- The mining company had to build a large dam to hold the tails from the gold mine.
- Environmental regulations require the safe disposal of tails to prevent toxic chemicals from leaching into the local groundwater supply.

## Examples

- I chose tails, but the coin landed on heads.
- We decided who would go first by flipping a coin; it came up tails, so Sarah started.
- The probability of a fair coin landing on tails remains exactly fifty percent, regardless of how many times heads has appeared in previous tosses.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.