| n. | 1. | the chemical symbol for copper. |
| Noun | 1. | Cu - a ductile malleable reddish-brown corrosion-resistant diamagnetic metallic element; occurs in various minerals but is the only metal that occurs abundantly in large masses; used as an electrical and thermal conductor Synonyms: atomic number 29, copper |
| 1. | (chat) | CU - "see you". | |
| 2. | (communications) | cu - Call Unix. | |
| 3. | (networking) | cu - The country code for Cuba. |