What does dissymmetry mean?
Dissymmetry is a formal noun describing a want of symmetry — a condition in which parts of a whole that might reasonably be expected to correspond fail to do so exactly. Unlike its everyday cousin 'asymmetry', which covers any absence of balance, dissymmetry often implies only a partial or subtle divergence from regular form, and it has historically been favoured in technical fields such as crystallography, optics, and engineering, where it could describe structures that were orderly overall yet not fully mirror-symmetric. The word derives ultimately from Greek roots meaning 'together' and 'measure', joined to the negative prefix 'dis-'. Today it is relatively uncommon outside specialist writing, but it remains useful when precision matters: it allows a writer to register a measured irregularity without suggesting chaos. Architects may invoke it to describe intentionally uneven façades, while scientists use it to characterize molecular or crystalline handedness.
nounThe state or quality of being unsymmetrical; a lack or breakdown of correspondence between parts that would otherwise be expected to match, often used of a slight or partial asymmetry rather than a complete absence of balance.
- A lack of symmetry; the condition of corresponding parts failing to match exactly.
- In older scientific usage (especially crystallography and optics), a structural difference such as chirality in which mirror-image forms are not superimposable despite overall regularity.
"A subtle dissymmetry between the building's two façades gives the structure an unexpectedly dynamic character."
"The engineer noted a slight dissymmetry between the load-bearing walls on either side of the hall."
"Pasteur's work on tartaric acid crystals revealed an optical dissymmetry that hinted at the handedness of molecules."
Usually treated as uncountable when referring to the general quality; pluralized mainly when discussing multiple specific instances in scientific writing.
"The survey catalogued several minor dissymmetries across the bridge's spans."
In crystallography, 'dissymmetry' once carried a precise technical meaning — a crystal could be perfectly balanced yet still dissymmetric, like your left and right hands.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of dissymmetry
Dissymmetry was formed in English from the prefix 'dis-' attached to 'symmetry', which itself comes from Latin symmetria and ultimately Greek symmetria ('agreement in measure, proportion'), from syn- ('together') and metron ('measure'). It entered English in the early nineteenth century, when scientific writers needed a term for partial or structural departures from symmetry, particularly in crystallography. Its cognates include 'symmetry', 'symmetric', and 'asymmetry', all built on the same Greek root.
Related word forms
How dissymmetry is actually used
Formal and somewhat rare; found chiefly in scientific, mathematical, and architectural writing. In everyday contexts 'asymmetry' is far more common. The term can carry a neutral or even positive connotation when the mismatch is deliberate or aesthetically interesting.
Easily confused with dissymmetry
Asymmetry is the general term for any absence of symmetry, while dissymmetry typically refers to a partial or slight departure from expected symmetry and is largely restricted to technical or scientific writing.