Definition & Meaning of "old bat"in English

What is the origin of the term "old bat" and how is it used?

"Old bat" is an English insult that dates back to the late 19th or early 20th century, using "bat" as a metaphor for someone seen as odd, erratic, or unpleasant, possibly influenced by associations with bats as eerie or unsettling creatures. The phrase came to describe an elderly woman who is cranky, unpleasant, or eccentric, often emphasizing irritability or meddling behavior. It is used in informal speech, usually in a disparaging or mocking tone. The term is clearly derogatory, combining age- and gender-based insult, though it is not strongly vulgar.