Plaid is an obstacle made of bamboo and iron bars, such as fences and prison partitions.
Aperture is a pillar, the same.
Without a deep image, pillars are used to rely on and look far. The railing is the railing, which can extend the connotation of yearning for the distant future and the return, but "railing" is meaningless.
Lattice, some poems can extend the meaning of barrier, which refers to a kind of object.