ENGLISH
REFERENCE

abaci

n. countable
C2 Proficiency abaci

n. the plural form of abacus. These are old tools with beads on wires that people use for counting and math.

n. the plural form of abacus, referring to manual calculating devices consisting of beads or stones moved along rods or grooves. This Latinate plural is less common in modern usage than the regularised 'abacuses'.


SIMPLE

The students practiced their math skills using wooden abaci.

CONTEXTUAL

The museum display featured several ancient abaci used by merchants across different centuries and cultures.

COMPLEX

While digital calculators have rendered manual tools obsolete in most classrooms, some traditional schools still teach the manipulation of abaci to help children visualize the base-ten number system.

Synonyms
Origin

From Latin abacī.

Usage

The plural form of 'abacus'. While 'abaci' follows Latin morphology, 'abacuses' is more frequent in contemporary English.

Pitfall

one abacione abacus'Abaci' is the plural form; the singular form is 'abacus'.

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