tetrahedron

English

A rotating tetrahedron

Alternative forms

• tetraedrum (obsolete)

Etymology

From Ancient Greek τετράεδρον (tetráedron, “triangle-based pyramid”), from τετράεδρος (tetráedros), from τετράς (tetrás, “four”) + ἕδρα (hédra, “seat”). By surface analysis, tetra- +‎ -hedron.

Pronunciation

• enPR: tĕtrəhē'drən, IPA^(key): /tɛtɹəˈhiːdɹən/

• Audio (US):

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• Audio (UK):

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Noun

tetrahedron (plural tetrahedrons or tetrahedra)

1. (geometry) A polyhedron with four faces; the regular tetrahedron, the faces of which are equal equilateral triangles, is one of the Platonic solids.

Derived terms

• hexatetrahedron
• icositetrahedron
• orthotetrahedron
• tetrahedral
• tetrahedrality
• tetrahedralizable
• tetrahedrally
• tetrahedrane
• tetrahedrite
• truncated tetrahedron

 

Translations

polyhedron

• Armenian: please add this translation if you can
• Belarusian: тэтра́эдр m (tetráedr), чатырохсце́ннік m (čatyroxscjénnik), чатырохсце́н m (čatyroxscjén)
• Bulgarian: тетраедър (bg) m (tetraedǎr)
• Catalan: tetràedre (ca) m, tetraedre (ca) m
• Chinese:

  Mandarin: 四面體／四面体 (zh) (sìmiàntǐ)

• Czech: čtyřstěn (cs) m, tetraedr (cs) m
• Danish: tetraeder n
• Dutch: viervlak (nl) n, tetraëder (nl) m
• Esperanto: kvaredro
• Finnish: tetraedri (fi), nelitahokas (fi)
• French: tétraèdre (fr) m
• German: Tetraeder (de) n, Vierflächner m
• Greek: τετράεδρο (el) n (tetráedro)
• Hebrew: ארבעון (he) m (arba'ón)
• Hindi: चतुष्फलक m (catuṣphalak)
• Hungarian: tetraéder (hu)
• Icelandic: ferflötungur m, fjórflötungur m
• Italian: tetraedro (it) m
• Japanese: 四面体 (ja) (shimentai), 三角錐 (ja) (sankakusui)
• Korean: 사면체 (ko) (samyeonche)
• Norwegian: tetraeder (no) n
• Persian: چهاروجهی (fa)
• Polish: czworościan (pl) m inan
• Portuguese: tetraedro (pt) m
• Romanian: tetraedru (ro) n
• Russian: тетра́эдр (ru) m (tetráedr), четырёхгра́нник (ru) m (četyrjoxgránnik)
• Spanish: tetraedro (es) m
• Swedish: tetraeder (sv) c
• Tagalog: patdayag
• Ukrainian: тетра́едр (uk) m (tetráedr), чотиригра́нник m (čotyryhránnyk)
• Vurës: wanagvet

regular tetrahedron

• Japanese: 正四面体 (せいしめんたい, seishimentai)