An Etymological Dictionary of the German Language/Ballast

by Friedrich Kluge

Ballast, m., ‘ballast,’ like other maritime expressions, from LG.; comp. Du. ballast, E. ballast. In MidHG. simply last, ‘ballast,’ whence the equiv. Fr. lest is derived. The first component of the compound is obscure; it is scarcely of Irish origin (Kelt. bal, ‘sand’), nor is it likely to be identical with OIc. bâra, ‘sea.’ On account of Dan. baglest, ‘ballast.’ the least improbable derivation is from bak, ‘back,’ discussed under Backe (1.). Ballast might perhaps be ‘load behind or in the rear.’