abacuses
n. countable C2 Proficiency UK //ˈæbɐkəsɪz// aba·cus·es
n. simple tools used for counting and math. They usually have a wooden frame with beads that slide along wires or rods.
n. manual calculating devices consisting of a frame with beads or balls that slide along parallel rods. Plural form of abacus.
The children learn to count using wooden abacuses.
Before electronic calculators became common, merchants in many parts of the world used abacuses to track sales.
While modern technology has largely replaced mechanical tools, some traditional schools still use abacuses to help students visualize the underlying principles of arithmetic.
Usage
The plural can be formed as 'abacuses' or the Latinate 'abaci', though 'abacuses' is more common in modern English.