Um may refer to:
- Um, an exclamation or filled pause in spoken conversation
- Um (Korean name)
- .um, the Top Level Domain for United States Minor Outlying Islands
- um for micrometre, sometimes written instead of the proper symbol µm in a limited character set
- -um-, an infix in many Austronesian languages
- Um interface, the air interface for the GSM mobile telephone standard
UM may refer to:
- Utilization management, is the evaluation of the appropriateness, medical need and efficiency of health care.
- UM (company), an advertising agency formerly known as Universal McCann
- Air Zimbabwe, IATA code UM
- United Methodist
- Unified Messaging
- The Union for the Mediterranean
- United States Minor Outlying Islands, ISO 3166 code UM
- Umphrey's McGee, a jam band
- Unified Model, a global numerical weather prediction model
Read more about Um: Universities