Meaning of vaporeon: any word with 8 or more letters.
Meaning of vapor, reon: any word with 5, 6 , or 7 letters.
Meaning of eon, vap, apr: any word with 3 or 4 letters.
Meaning of on, ap: any word with 2 or less letters.

How can you tell
You can tell by the voice
Like if a vapreon said
On vap
In a scared voice means I'm out