dirk

In half a minute he had reached the port scuppers, and picked, out of a coil of rope, a long knife, or rather a short dirk, discolored to the hilt with blood.

The word dick itself serves as model for two variants which are probably Midwestern, dirk and dork, also meaning "penis"...

...on at least one Midwestern campus a dirk may be an "oddball" student, while a prick (more common) is of course an offensive one.