Ninja Geohasher
From Geohashing
A Ninja Geohasher is someone who goes to geohashes but doesn't document their expeditions on the wiki. These people may believe that it's not a meetup because they didn't meet anyone, may not be comfortable with the technology or with publishing their information on the web, or may just be too tired after their expeditions to write them up.
For obvious reasons we have no way of knowing how many ninja geohashers there are. Just remember that they may be out there, so be sure to look for and leave markers at your geohashes and try to be there at 4 p.m.