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# tetra

noun (a tetra, tetras); also a prefix tetra- meaning four

«tetra» in the English dictionary: everyday and in Jewish tradition — its meanings, how the lessons use it, and examples, each with its tree on Mova.

## Everyday

1. A tetra is a small, often brightly coloured freshwater fish from South America or Africa, popular in home aquariums, such as the neon tetra. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#m1)
2. Tetra- at the start of a word means four, as in tetrahedron (a solid with four faces) and tetrapod (an animal with four limbs). [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#m2)

### In the lessons

In everyday life tetras are pet fish kept in tanks. In maths and science the prefix tetra- signals the number four. Phrases: neon tetra, a shoal of tetras, tetrahedron.

### Examples

- We have six neon tetras in our fish tank. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x1)
- Tetras like to swim together in a shoal. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x2)
- A tetrahedron is a pyramid with four triangle faces. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x3)
- The neon tetra has a shiny blue stripe. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x4)
- Frogs, lizards, birds and people are all tetrapods. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x5)
- Feed the tetras a small pinch of flakes. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x6)
- The pet shop sells tetras, guppies and goldfish. [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/#x7)

### Note

Countable: one tetra, two tetras. In maths, tetra- = 4 (tri- = 3, penta- = 5). Tetra Pak is a brand name for drink cartons, not a fish.

## In Jewish tradition

In everyday life tetras are pet fish kept in tanks. In maths and science the prefix tetra- signals the number four. Phrases: neon tetra, a shoal of tetras, tetrahedron.

### Examples

- Rittangelius gives "credidit in Tetra- grammaton," but this word is not in the Hebrew. (Sefer Yetzirah, Westcott 1893) [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/judaism/T/tetra/#x1)
- The vowel letters, however, the letters of the Tetra- grammaton, are images and pictures of superior angels. (Mordell, The Origin of Letters and Numerals according to Sefer Yetzirah (1914)) [tree →](https://mova.elamur.ai/free/en/corpora/dictionaries/judaism/T/tetra/#x2)

### Note

Countable: one tetra, two tetras. In maths, tetra- = 4 (tri- = 3, penta- = 5). Tetra Pak is a brand name for drink cartons, not a fish.

## On Mova

- [Trees and pragmatics of «tetra» in the school dictionary](https://mova.elamur.ai/free/en/corpora/dictionaries/school/T/tetra/): every meaning and example parsed by Mova, with its dependency tree and frames.
- [«tetra» in the school dictionary](https://mova.elamur.ai/free/en/dictionaries/school/w/tetra.html) on Mova free.
- [Trees and pragmatics of «tetra» in the Judaism dictionary](https://mova.elamur.ai/free/en/corpora/dictionaries/judaism/T/tetra/): every meaning and example parsed by Mova, with its dependency tree and frames.
- [«tetra» in the Judaism dictionary](https://mova.elamur.ai/free/en/dictionaries/judaism/w/tetra.html) on Mova free.