undrain

From un- +‎ drain.

undrain (third-person singular simple present undrains, present participle undraining, simple past and past participle undrained)

1. To restore that which has drained away.
   • 1970, John R. Niland, The Asian engineering brain drain, page 7:

     The probable differences between gross and net drain also require an explanation of why some manpower "undrains" by returning home after a period of working in the United States.

   • 2000, The American Benedictine Review - Volume 51, Issue 3, page 290:

     On this score, monastics are will-positioned, in that one of the purposes of monastic work was to recreate the garden of paradise. The Cistercians, however, have not made a move to undrain the swamps.

   • 2018, Betsy Beyer, Niall Richard Murphy, David K. Rensin, The Site Reliability Workbook: Practical Ways to Implement SRE, →ISBN:

     Remove the repair reason, clear the problem from the database, and undrain the switch.

undrain (plural undrains)

1. A water collection system that drains water away from a location.
   • 1911, Engineering and Contracting - Volume 36, page 307:

     The experiments with fresh and septic sludge show that for filters of the same size material, fresh sludge passes through into the undrains while septic sludge merely gives up its water.

   • 1952, Pennsylvania water works operators' association, Journal - Volumes 24-34, page 25:

     New undrains, gravel retaining screens and air wash systems were installed.

   • 1993, Loren Runar Anderson, Geotechnical practice in dam rehabilitation:

     Absence of filtered undrains beneath spillways or behind walls.