Definition of trihedron in English:
 trihedron
nounPlural trihedra, Plural trihedronstrʌɪˈhiːdrəntraɪˈhidrən
A solid figure having three sides or faces (in addition to the base or ends).
 Example sentencesExamples
-  Besides chopping-tools, polyhedrons and some cleavers, trihedrons and bifaces form the most characteristic element within the tools.
 -  A hollowed trihedron replica is thus obtained having exactly the same shape as the model.
 -  However, these trihedra were much larger and were growth defects which arose from a mechanism other than the condensation of vacancies or the release of misfit strain.
 -  A set of possible initial registrations is generated searching and aligning pairs of compatible trihedra from different views.
 -  A line making equal angles with the edges of a trihedron is called an isoclinal line of the trihedron.
 -  Instead of vector components the orthonormal trihedrons of coordinate systems are subjected to transformations.
 -  From now on, we will move trihedrons to restore their positions and colors, without moving dihedras.
 -  If this antenna is perfect, the axes of the two trihedrons would be respectively parallel to each other.
 
Origin
  
Early 19th century: from tri- 'three' + -hedron, on the pattern of words such as polyhedron.
   Definition of trihedron in US English:
 trihedron
nountrīˈhēdrəntraɪˈhidrən
A solid figure having three sides or faces (in addition to the base or ends).
 Example sentencesExamples
-  A set of possible initial registrations is generated searching and aligning pairs of compatible trihedra from different views.
 -  However, these trihedra were much larger and were growth defects which arose from a mechanism other than the condensation of vacancies or the release of misfit strain.
 -  From now on, we will move trihedrons to restore their positions and colors, without moving dihedras.
 -  A hollowed trihedron replica is thus obtained having exactly the same shape as the model.
 -  Instead of vector components the orthonormal trihedrons of coordinate systems are subjected to transformations.
 -  If this antenna is perfect, the axes of the two trihedrons would be respectively parallel to each other.
 -  A line making equal angles with the edges of a trihedron is called an isoclinal line of the trihedron.
 -  Besides chopping-tools, polyhedrons and some cleavers, trihedrons and bifaces form the most characteristic element within the tools.
 
Origin
  
Early 19th century: from tri- ‘three’ + -hedron, on the pattern of words such as polyhedron.