code

1. A short symbol, often with little relation to the item it represents.

   This flavour of soup has been assigned the code WRT-9.

2. A body of law, sanctioned by legislation, in which the rules of law to be specifically applied by the courts are set forth in systematic form; a compilation of laws by public authority; a digest.
3. Any system of principles, rules or regulations relating to one subject.

   The medical code is a system of rules for the regulation of the professional conduct of physicians.

4. A set of rules for converting information into another form or representation.
5. A message represented by rules intended to conceal its meaning.
6. A cryptographic system using a codebook that converts words or phrases into codewords.
7. Instructions for a computer, written in a programming language; the input of a translator, an interpreter or a browser, namely: source code, machine code, bytecode.

   I wrote some code to reformat text documents.

8. (scientific programming) A program.
9. A particular lect or language variety.
10. An emergency requiring situation-trained members of the staff.

1. To write software programs.

   I learned to code on an early home computer in the 1980s.

2. To add codes to a dataset.
3. To categorise by assigning identifiers from a schedule, for example CPT coding for medical insurance purposes.
4. To encode.

   We should code the messages we send out on Usenet.

5. To encode a protein.
6. To call a hospital emergency code.

   coding in the CT scanner

verb

Of a patient, to suffer a sudden medical emergency (a code blue) such as cardiac arrest.