Unit of measure
U medical abbreviation
U means "unit".
On The Joint Commission's Do Not Use list. ISMP suggests: Write "unit" or "units".
Each meaning matched at least two public references (5 in all for U), checked October 23, 2026. The table lists them.
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What U means
| Meaning | Latin origin | Where used | Checked against |
|---|---|---|---|
| unit | None | Prescriptions, Charting |
Example
Training example of a Do Not Use entry: "U" written after a number on an order.
A made-up line that shows the abbreviation in place. It is not about any patient and is not an instruction.
Related abbreviations
Elsewhere on Rivvi
Questions
What does U mean in medical terms?
U means "unit".
Where is U used?
U shows up in prescriptions and charting. Its category here is unit of measure.
Is U on the Joint Commission Do Not Use list?
Yes. The Joint Commission's Do Not Use list includes U. ISMP's suggested practice: Write "unit" or "units".