2521: abacus Nov 7, 2021

The word 'abacus' came to English from Latin hence the plural 'abaci', but this word might really have a semitic origin. While now the term is used exclusively to refer to the mathematical instrument, it used to be more generic, denoting many types of boards including board-game boards and sand tables, as with the Ancient Greek ἄβαξ (ábax). This has been likened to the Hebrew אבק‎ (āvāq) meaning 'dust' which would explain the senses of the Catalan 'àbac' meaning both 'mathematical table' and 'board covered in sand'.