quail

From Middle English quaylen, from Middle Dutch queilen or quēlen, from Old Dutch *quelan, from Proto-West Germanic *kwelan, from Proto-Germanic *kwelaną, meaning "to suffer." It's a doublet of queal.

The word carried a sense of suffering or wasting away before narrowing into the more specific feeling of flinching or losing courage that we use today.

It shares a root with the rarer English word queal, both descending from the same Proto-Germanic word for suffering.