ACO, AcO, or Aco may refer to:
Acoustics is the interdisciplinary science that deals with the study of all mechanical waves in gases, liquids, and solids including topics such as vibration, sound, ultrasound and infrasound.
Acoma Pueblo (/ˈækəmə/; Western Keresan: ʔáák’u; Zuni: Hakukya; Navajo: Haak’oh) is a Native American pueblo approximately 60 miles (97 km) west of Albuquerque, New Mexico in the United States.
Acorn Computers Ltd. was a British computer company established in Cambridge, England, in 1978. The company produced a number of computers which were especially popular in the UK, including the Acorn Electron and the Acorn Archimedes.
Aconitum (/ˌækəˈnaɪtəm/), commonly known as aconite, monkshood, wolf's bane, leopard's bane, mousebane, women's bane, devil's helmet, queen of all poisons, or blue rocket, is a genus of over 250 species of flowering plants belonging to the family Ranunculaceae.
An acoustic metamaterial is a material designed to control, direct, and manipulate sound waves as these might occur in gases, liquids, and solids.
The Acorn Electron is a budget version of the BBC Micro educational/home computer made by Acorn Computers Ltd.
Acomb /ˈeɪkəm/ is a suburb within the City of York Unitary Authority, to the western side of York, England.