Since it's written in Katakana, I would presume that word is adopted from another language. Because if it were native it would be more properly written in Hiragana, if a Kanji character didn't exist.
If the borrowed word is English
(and it very well may not be), then my best guess would be that this is a contraction of "Hand Pull". The meaning from there is self explanatory.
{edit} Google~Fu says Hanpuru is a Basque word that means Tumor. Interesting, but unhelpful in this case...
