ultra-fine lattice; very fine latticework
Refers to an extremely fine lattice, often used in traditional Japanese architecture for windows or screens. The name literally means 'insect cage lattice', suggesting a mesh fine enough to keep insects out.
The ultra-fine lattice of this temple has beautiful delicate woodwork.
I look at the garden through the very fine lattice.
格子 is a general term for lattice or grille. 虫籠格子 specifically refers to an extremely fine variety, much denser than ordinary lattice.
Compound of 虫籠 (mushikago, 'insect cage') and 格子 (kōshi, 'lattice'), referring to a lattice so fine it resembles an insect cage.