hyperfocal distance: the distance in front of a lens that is focused at infinity beyond which all objects are well defined and clear
distance: the property created by the space between two objects or points
erythroblastosis fetalis: severe anemia in newborn babies; the result of Rh incompatibility between maternal and fetal blood; typically occurs when the child of an Rh-negative mother inherits Rh-positive blood from the father; can be diagnosed before birth by amniocentesis