Well dear u have asked a very philosophical question but i still will love answering it in my biology way . Actually the orange color was named after the fruit and not the fruit after the color . The color name was actually the fruit name before the color name was decided , so when the fruit was named , no orange color name was there . .After watching the fruit color , they remembered that the refracted light of prism they got i.e , white light has same color and they named it on the name of fruit .
Moreover orange is green in color at early stage but still its called a orange and why apple is not called apple in color because red color was named way before apple was named . So red color exists before apple .
and actually both these names are not the original names of these fruits , the original names are the scientific names which are used all over the world ,
Scientific Name For Apple - Malus domestica
and
Scientific name of orange - Citrus sinensis
which don't have any relation with color . So as explained name ad color are different and have no relation . Hope my answer made sense and one more reason apple is of various colors , so it can't be named on color actually .