Glossary: O

A   B   C   D   E   F   G   H    I   J   K   L   M   N   O   P   Q   R   S   T   U   V   W   X   Y   Z   OHCA (Off Hook Call Announce)   Allows a user to inform a busy extension that another call is waiting by talking through the built-in speaker of the called party's proprietary extension. Outward Dialing Allows you to make a call to an outside party.