Um or UM may refer to:
Businesses and organisations
Air Zimbabwe (IATA:UM) Union for the Mediterranean, an intergovernmental body United Methodist Church United Motors Company, an American automotive parts supplier Universal McCann, a global advertising and media agency Universal Medicine, an Australian cult
Language "Um", a filler in spoken English and some other languages Um (cuneiform), an ancient alphabetic symbol
Science and technology Micrometre (μm), sometimes written as "um" in limited character sets Ultrarapid metabolizer, a term used in pharmacogenomics to refer to individuals with substantially increased metabolic activity .um, the Internet domain for the US Minor Outlying Islands Um interface, the air interface for the GSM mobile telephone standard Unified Model, a global numerical weather prediction model User manual, a document or manual intended to give assistance to people using a particular system Utilization management, the evaluation of the appropriateness, medical need and efficiency of health care
Other uses Um (Korean surname) Umphrey's McGee, a jam band, stylized as UM Unified Messaging, in marketing United States Minor Outlying Islands (ISO 3166:UM) Unofficial magistrate, as a postnominal Uttaradi Math, a Hindu matha (monastery)