Final answer:
The prefix 'pan-' means 'all' and is used to describe a collective or comprehensive group, such as Pan-Africanism for all African nations and peoples, or the Pantheon representing all gods of a certain region.
Step-by-step explanation:
The prefix pan- originates from Greek and signifies 'all' or 'encompassing everything'. When attached to words, it expands their meaning to include all members of a group.
For instance, Pan-Africanism refers to political and cultural movements aimed at unifying all African nations and people of African descent around the world. Similarly, the term Panhellenic describes all people of Greek ancestry or origin, whether they reside in Greece or not. Lastly, the word pantheon combines 'pan-' with 'theos' (meaning gods) to denote all the gods of a particular group or region. Hence, the prefix pan- is associated with unity and the inclusion of every member within a certain category.