What does kilo mean?
A kilo is a unit of mass equal to 1,000 grams, commonly used in everyday speech as the familiar counterpart of the formal term “kilogram.” The word is especially common in British and other varieties of English, though it is understood internationally. People use it with food, luggage, animals, and body weight: “a kilo of apples,” “a two-kilo bag,” or “she lost three kilos.” In less formal contexts, “kilo” can also mean a thousand of something, although this usage is more likely to sound playful or approximate. In scientific, technical, and official writing, “kilogram” or the abbreviation “kg” is generally clearer and more appropriate. The term derives from the prefix kilo-, meaning one thousand, and is related to words such as kilometer, kilowatt, and kilobyte.
nounA unit of mass equal to 1,000 grams, used in many countries as the everyday term for kilogram. Informally, it can also mean a thousand of something.
- A unit of mass equal to 1,000 grams, commonly used as an abbreviation for kilogram.
- Informally, a thousand of something, especially when referring to a quantity of objects or a group of people.
- An amount of body weight measured in kilograms.
"She bought a kilo of tomatoes at the market."
"The parcel weighs just under two kilos."
"The stadium was filled with kilos of supporters waving flags."
“Kilos” is the usual plural in contemporary informal usage; “kiloes” follows the pronunciation of the ending more explicitly and is also standard.
"The workers carried several kilos of equipment."
The word comes from the Greek word for “thousand,” so a kilo was originally a convenient way of saying “a thousand grams.”
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does kilo come from?
The word comes through French kilo-, from the Greek khīlos, meaning “thousand.” The combining form was adopted in the metric system to indicate units equal to a thousand of a smaller unit. Modern usage developed especially for the kilogram, while related forms such as kilometer and kilowatt use the same thousand-forming prefix.
How kilo is actually used
“Kilo” is informal or familiar, especially in British, Australian, New Zealand, and South African English. In formal scientific and commercial contexts, “kilogram” or the symbol “kg” is preferred. The plural is “kilos”; “kiloes” is also accepted but less common.
Easily confused with kilo
A kilo generally refers to a kilogram in everyday speech, whereas a kilobyte is a unit of digital information.