What is a four-tined fork called if a three-tined fork is a trident? Serious and not so serious answers welcomed!

quadrident.

3780 hits on Google.

Here’s a commercial instance:

IMERSION – Underwaters sports – SPEARFISHING SPIRIT

The Coralign brand has a large variety of differents accessories tridents and quadridents to fit the threaded 6 X 100 shafts.