First, there is no grammatical form called the “ablative” in English.

An agentive suffix is also called “-er”. This may be occasionally misleading, since it does not necessarily indicate agents, but that’s the best term I’m aware of. Most English speakers would no call it an agentive suffix, though, they’d just call it “a suffix” or “the -er ending”.

An adjective attaches only to verbs, so -> travel -> traveler -> and journey -> journeyer are -> fine except exodus -> by the verb. exoduser is permissible, since exodus is not a verb.

Is there derivation and not inflection when a name is used? What makes a traveler is a different word from travel to travel the world?

So traveler is not considered as the “anything” of travel, but as agentive which is derived from Travel.

This distinction is to some degree arbitrary but very well established.

Are the Exodus not Greek or Latin?

Two likely Latin verbs to use instead of

exire are exeo, exivi(ii), exitus – come/go/sail/march/move out/forth/away,

leave

and fugio, fugere, fugi, fugitus – flee, fly, run away; runaway from

profugus, profugi (noun) – exile; fugitive;

refugee; runaway A nice Latin-English bilingual dictionary can be explored here

Net/search/latin/profugus/profugus/linn.Net/reference/site/index/profugus.html

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