the.com/foster parent

means An adult who takes a child into their home and care on a temporary, legally-sanctioned basis, without being the biological or adoptive parent.

from Foster traces back to Old English 'fostor,' meaning food or nourishment, rooted in 'fostrian' — to feed, support, or rear. Long before it meant paperwork and placement agencies, it simply meant to sustain life. The 'parent' half is pure Latin, from 'parens' — one who brings forth. So at its root, 'foster parent' means almost exactly what it still does: someone who nourishes a child they did not bear.