What does triclinic mean?
Triclinic describes the least symmetrical of the seven crystal systems. In a triclinic crystal, the three crystallographic axes have unequal lengths, and no pair meets at a right angle; the interaxial angles are therefore oblique rather than perpendicular. This geometry gives triclinic crystals very low internal symmetry compared with systems such as cubic or orthorhombic. The word commonly appears in phrases such as “triclinic structure,” “triclinic lattice,” and “triclinic crystal system.” Mineralogists and materials scientists use it to classify crystalline substances and relate their structures to observable properties. Although triclinic is technically an adjective, it is also widely understood as a noun naming the crystal system itself. The term is primarily formal and specialized, and its unusual combination of an unequal-axis geometry and oblique angles makes it a distinctive example of scientific vocabulary.
adjectiveRelating to or constituting the triclinic crystal system, in which the three crystallographic axes are of unequal length and no two are perpendicular.
- Of or relating to a crystal system characterized by three unequal crystallographic axes, no two of which are perpendicular.
"Quartz has a triclinic crystal structure despite lacking a centre of symmetry."
"The mineral was identified as having a triclinic structure consistent with its optical properties."
"In crystallography, the triclinic system allows the least symmetry of all the crystal systems."
A triclinic crystal is the geometrical opposite of a perfect grid: its three axes point in three different, non-right-angled directions.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does triclinic come from?
Triclinic combines the Greek-derived prefix tri-, meaning “three,” with the combining form -clinic, based on Greek klinē, meaning “slope.” The elements refer to three inclined crystallographic axes: the axes have unequal lengths, and none is perpendicular to another. The construction reflects the naming pattern of related crystal-system terms such as monoclinic.
How triclinic is actually used
A specialized term used principally in crystallography, mineralogy, materials science, and related fields. It normally appears in formal or technical writing rather than everyday speech.
Easily confused with triclinic
A triclinic crystal has no two crystallographic axes perpendicular, whereas a monoclinic crystal has two perpendicular axes and one inclined axis.