Satu

Satu is the standard word for the numeral one in Indonesian and Malay, the official languages of Indonesia and Malaysia. It functions as a cardinal numeral to denote a single unit and is used in everyday counting and measurement, as in satu buku (one book), satu hari (one day), or satu liter air. It also appears in compounds and phrases that express unity or single identity, such as satu tujuan (a single goal), satu hati (one heart), or satu suara (one voice).

Linguistically, satu belongs to the Austronesian language family, within the Malayic branch. It has cognates across the Malay-speaking world, and related languages in the region use different forms for the same concept. For example, neighboring languages often have distinct words for “one,” such as Javanese siji and Sundanese hiji, which illustrate regional variation despite shared roots in the broader language family.

In common usage, satu also appears in idioms and expressions that emphasize unity, wholeness, or sequential emphasis, including phrases like satu-satu (one by one) and satu sama lain (each other). Beyond ordinary speech, it is encountered in education, media, and governance as a basic numeral and as a building block in more complex expressions.