IPA: /ˈwɔːtər/
KK: /ˈwɔːtər/
A tool or device that provides water for animals or plants to drink.
The farmer installed a new waterer in the field to ensure the animals had enough to drink.
Waterer → It is formed from "water" (from Old English *wæter*, meaning liquid that falls as rain or is found in rivers and lakes) and "-er" (meaning a person who). The word "waterer" refers to a person who waters plants or provides water.
Think of someone who provides 'water' — that's what a 'waterer' does, and the '-er' just means a person.