Yes, it can be (a hollow sphere, a hollow sound). The word hollow can also be a noun, meaning a gap, void, or a small valley.
One word with the prefix "coel" meaning hollow is "coelom," which refers to the body cavity in certain animals where the internal organs are located.
semblance
core, bore, hole,
Either how things look, as in "it has a very twisted appearance", or when soemthing arrives, as in "she made a late appearance".
grandeur
appearance
The word "cave" is of Latin origin, derived from the Latin word "cavus" meaning hollow.
a prefix meaning 'cell' as in cytoplasm. The origin is Greek 'Cutos' meaning a vessel or container
From Latin Idolium meaning image. Also the Greek word Eidolon, meaning 'appearance, phantom, mental image or statue
The meaning of the word cleavage means a split or a separation, a division or a cleft. Another meaning of the word cleavages refers to the hollow between the breast of a female and it is said that they are "revealing their cleavage" if they wear a low cut top.
The word for "to change" is "transform," meaning to make a thorough or dramatic change in form, appearance, or character.