Answer:
the secret languages used for communication.
Explanation:For instance, the language Navajo helped U.S Marine Corps to transmit coded messages without any breach with the help of U.S natives, who used their expertise in this language
A strong flood or a rush of water is called a cataract or a large waterfall.
I do not wanna say the wrong thing or youse the wrong words so the answer is on google I am 100% sure :)