1650s, "a settling to the bottom," from Latin subsidentia "a settling down," from subsidens, from subsidere (see subside (v.)).
Entries linking to subsidence
subside v.
1680s, of objects, "to sink to the bottom," from Latin subsidere "sit down, settle, sink, fall; remain; crouch down, squat," from sub "under, beneath" (see sub-) + sidere "to settle," related to sedere "to sit," from PIE root *sed- (1) "to sit." Of liquid surfaces, "to sink to a lower level, be reduced" from 1706. Related: Subsided; subsiding.