D&D 5E What does the "- " mean beside some of the weapons? :)

[Ancalagon]

The wikipage does say "one or more spike"

What I'm finding interesting is that the 3.x morning-star could do blundgening or piercing damage, and the best way to have that happen is with a one spike design. However the illustration matched the "spiky club/mace" concept. In 5e it's piercing only.