Loops on Project-GC is used when talking about fulfilling the requirements for a diamond badge one more time or filling a matrix or grid one more time. For example, if a user has found three caches for every square in the D/T grid the user has three D/T loops. Users with multiple loops are referred to as loopers on the site.
39 of the 45 badges can be looped.
The 360 from home tools supports looping.