hollow object
nounUK /ˈhɒləʊ ˈɒbdʒɪkt/
US /ˈhɑːloʊ ˈɑːbdʒekt/
A hollow object is a thing that is empty inside.
The bird built its nest inside a hollow object like an old log.
OTHER MEANINGS
2. An object with a space or gap inside it rather than being solid.
A drum is a hollow object that makes sound when you hit it.
3. Something that looks solid but has nothing inside.
The chocolate bunny was a hollow object, so it broke easily.
4. A container-like thing whose inside is open or empty.
She hid her treasure in a hollow object in the garden.