barbs: A sharp protrusion of the blade of
stemmed or notched types at the proximal corners.
There are 6 major types of barbs, Expanded which means
flaring outward and upwards towards the distal end, Horizontal which
means flaring outward at 90 degrees to the stem, Inversely Tapered
which means pointing downward and getting thinner, Rounded which means
the outline is semi-circular, Struck which means knocked off, and
Tapered which means minimized in an angle towards the tip.
Glossary of Lithics