the trademark "Panasonic" was used in Japan in p>1986. From the word itself, "Pana-" means "all, all in all" and "-sonic" means sound. The whole word means all sounds.
It is an action that many enterprises have done to make meaningful trademarks meaningless. Using a meaningless name can make the extension of its brand wider, so in fact, "Panasonic" itself is a name with no exact meaning.