An Etymological Dictionary of Astronomy and Astrophysics

1. General: A father or a mother. A precursor, or
   → progenitor.
   

2. Physics: A → nuclide that upon → radioactive decay or → disintegration yields a specific nuclide (the → daughter). See also → parent cloud, → parent element, → parent galaxy, → parent molecule.

Etymology (EN): From O.Fr. parent, from L. parentem (nominative parens) “father or mother, ancestor,” from parere
“to bring forth, give birth to, produce,” from PIE base *per- “to bring forth”

Etymology (PE): Permâr, literally “father-mother” (as in Sogd. māt-pitri “parent”),
from Gilaki per, → father, + Gilaki mâr, → mother.