parent bird
Refers to a bird that is a parent, often in contrast to its chicks or eggs. Used in both literal and figurative contexts.
The parent bird is bringing food to its chicks.
I found a parent bird warming its eggs.
ひよこ is a baby chick, while 親鳥 is the adult parent bird that has grown past that stage.
Compound of 親 (oya, 'parent') and 鳥 (tori, 'bird'), with rendaku voicing of とり to どり.