c.m.

1. church missionary.

2. common meter.

3. corresponding member.

4. court-martial.

* * *

cm. or cm (no period),

centimeter or centimeters.

c.m.,

an abbreviation for the following:

1. church missionary.

2. circular mill.

3. corresponding member.

4. countermarked.

Cm (no period),

curium (chemical element).

CM (no periods),

1. command module.

2. Common Market.

3. court-martial.