chiasmata
|chi-as-ma-ta|
/kaɪˈæzmətə/
(chiasma)
X-shaped crossing
Etymology
'chiasma' originates from Greek, specifically the word 'chiásma' (χίασμα), where the root 'chi-' referred to the Greek letter 'chi' (χ) indicating an X-shaped crossing.
'chiasma' passed into Late Latin and New Latin as 'chiasma' and was adopted into English (plural 'chiasmata') in scientific and rhetorical usage in the 19th century.
Initially, it meant 'a crossing or X-shaped mark'; over time it evolved into specialized uses meaning 'a crossing of fibers' in anatomy and 'a site of genetic exchange' in genetics, while retaining rhetorical senses related to structural inversion.
Meanings by Part of Speech
Noun 1
plural of 'chiasma'; in genetics, the sites where paired chromatids exchange genetic material (crossing-over points) during meiosis.
During prophase I, visible chiasmata indicate where crossing-over has occurred between homologous chromosomes.
Synonyms
Noun 2
plural of 'chiasma'; in anatomy, points where nerve fibers cross, as in the optic chiasm (multiple such crossings).
Researchers examined the chiasmata in the brainstem to study patterns of fiber decussation.
Synonyms
Noun 3
plural of 'chiasma'; in rhetoric/literature, points of reversal or crossing structure (related to chiasmus), where elements are arranged in an ABBA pattern.
The poet's lines contain several chiasmata that invert the expected word order for emphasis.
Synonyms
Last updated: 2025/09/22 06:49