Board Thread:General Discussion/@comment-121.217.192.71-20140128071633/@comment-3250527-20140919021333

The reason why it is called a spear is because of its description in the light novel, and Kawahara (the author) used the kanji 短槍, with furigana ショートスピア (shōto supia, short spear).

Here is also a quote from the novel:

Volume 8, A Murder Case in the Area, Part 2: The entire spear was made from black-colored gold, and this kind of weapon was really rare. Its length was probably about 1m, and the base had a grip about 30cm long. At the tip of the handle, there was a 15cm long blade.

Also, I don't recall most swords having an end spike/blade.