Butterfly refers to a method of cutting food partially through and spread open to increase the surface area.
It is usually done when cooking shrimps
See also:
"Butterfly" is in the HS Code "9507"
Fishing Rods, Fish-Hooks And Other Line Fishing Tackle; Fishlanding Nets, Butterfly Nets And Similar
"Butterfly" is in the UNSPSC Code "21102403"
Butterfly breeding equipment