# description
Indicates the type of use for which the code is defined.

# concept[].definition
The code is an alternative code that can be used in any of the circumstances that the primary code can be used.

# concept[].definition
The code should no longer be used, but was used in the past.

# concept[].definition
The code is an alternative to be used when a case insensitive code is required (when the primary codes are case sensitive).

# concept[].definition
The code is an alternative to be used when a case sensitive code is required (when the primary codes are case insensitive).

# concept[].definition
The code is an alternative for the primary code that is built using the expression grammar defined by the code system.