In season 1, episode 13 called Mystery at the Lighthouse of the TV series Pokémon the meaning is briefly discussed by Bill (a Pokémon researcher), and questioned by Jessie (one of the show's villains).
Bill, who is dressed up as an extinct Pokémon begins to talk about how his cosplay helps him to learn how extinct Pokémon use to live. He notes that there are over 150 distinct Pokémon, and there are others waiting to be discovered. This leads to the following conversation about meaning.
Bill: There is always something new to look for in our lives and in ourselves. Ash: Something to look for? Bill: Yes, there is a lot for us to look for inside and outside of ourselves. There is meaning for every creature. A meaning for all the Pokemon and a meaning for all us humans too.
Ash: A meaning for all.
The scene cuts to James, Jessie, Meowth climbing a cliff in order to steal Pokémon.
Jessie: Sometimes I wonder what the meaning of it all is. Why do I go to all this trouble just to be bad? James: It's so we can get other people's Pokemon.
In philosophy, many never discuss the meaning of life beyond Homo sapiens. However, I would surmise that if humans have meaning, so do other creatures. What do you think? Do sentient beings only live meaningful lives, or is it possible for other creatures to live meaningful lives as well? If so, at what point would a life stop being meaningful... a dog, a cat... a frog, bacteria... a virus?
This is of course not the first time we've seen villains in TV series question the meaning of life. Check out the "evil" tag to find other blog posts about the topic.