The shell bone script of character Dragger is
The character has two meanings:
1, the dragger if it is an independent character, or used in word 匕首.
2, a person if it is part of a character.
How did the character have Dragger meaning? Probably there was some draggers in the ancient time which have this kind shape.
The situation is similar to character 月: which means Moon if it is used as a character, but means Body, or Organ or Meat if it is a part of a character.