IPA: /ˈskriːtʃər/
KK: /ˈskriːtʃər/
A person or thing that makes a loud, high-pitched noise, often in a distressing or alarming way.
The screecher in the tree startled everyone with its loud calls.
Screecher → It is formed from "screech" (from Middle English *screchen*, meaning to cry out or scream) and "-er" (meaning a person who). A screecher is a person or thing that makes a loud, shrill cry or scream.
Think of someone who 'cries out' ('screech') loudly — that's why a screecher is someone who makes a loud noise.