Reference for Bekhorot 49:12

הלכה כרבי שמעון

Has it not been taught: If one plucks a large feather from the wing [of a bird] and cuts off [its head], and smooths<span class="x" onmousemove="('comment',' Tearing the hair from the windpipe and smoothing it away from the sides.');">⁸</span>

Jastrow

Jastrow