well some word like dog-food and cat-fish
are named by their looks, feel, or even what they are used for.
The water cycle — technically known as the hydrological cycle — is the continuous circulation of water within the Earth's hydrosphere, and is driven by solar radiation. This includes the atmosphere, land, surface water and groundwater.
Explanation:
A nomad (Middle French: nomade "people without fixed habitation") is a member of a community without fixed habitation which regularly moves to and from the same areas. Such groups include hunter-gatherers, pastoral nomads (owning livestock), and tinkers or trader nomads.
Hope this helps..