To hollow out is to make something hollow, to make it have a hole or a space inside. When you hollow out a tree, you make a hole in it so that you can get at the wood inside.
The tree was hollowed out by the wind.
The tree was hollowed out by the woodpecker.
verb
To make a hole in something; to excavate
verb
To call or urge by shouting; to hollo.
1
The hole was hollow.
2
The balls are hollow and have two small antipodal holes.
3
A sprayer has a hollow housing with an inlet port and an outlet opening.
4
He hides the body in the hollow of a tree and cements up the opening.
5
The atomizer includes a hollow piston having a hollow piston rod.
6
Overburden is deposited in nearby valleys and hollows.
7
Hollow and interspaces are the results of the form of the installations.
8
The body of the instrument is made of a hollow gourd.
9
A sprayer is connected to the hollow carrying handle and to the reservoir.
10
It builds nests in tree hollows or litter of epiphyte.