Actually the Indian Gir Lion does live in jungle/forest. As for the history of the word, the present meaning (forest) might’ve been used for longer by now (in India) than the old meaning.
And funnily enough, the Hindi word “sher” can mean either lion or tiger, although they do have a specific word for tiger, “bagh”. And we do have the same title/phrase in Hindi which could mean either lion or tiger is the king of the jungle. I personally never thought it was the tiger because when I was a child, the Lion King had already been released.
The major difference is compressibility. Generally, liquids are practically incompressible. So just knowing the mass flow rate and density, volume flow rate can be calculated. It’s not so simple for gases