dead sword hilt semantics

[Elmereya]

good afternoon, on some swords of this type there is such a sign on the defense, which is the main decorative element in the design of the hilt, or an independent element,
question: is there an understanding of what this symbol means?
in the collage, the top two hilts are attributed to Cromwell. collected from the Internet.
with respect, and I wish you all good health