Outdoor relief seems to be some sort of welfare program. In the second volume, 1898-1937, there is a field "Cause of Destitution". At the top of the pages, there is printed "Outdoor Relief granted by the Directors of the Poor of Lancaster Co."
"Outdoor relief granted by the Directors of the Poor. Includes records of the Columbia Outdoor Relief, patient lists for Allentown, Norristown and Harrisburg State Hospitals, Selinsgrove, Polk and Pennhurst State Schools, Evelyn Training School, and the Pennsylvania Children's Aid Society, and a list of quarantined families."
Two volumes: 1885-1893 (includes index) & 1898-1937 (no index). Arranged by date and district.
See the Lancaster County Almshouse and Hospital Collection, MG-277, for similar records.