Balachandran V's "Definition" argues that putting a label on something shrinks it. The speaker plays on the sound and sense of the word itself: to define is to confine, to make something finite. Each line in the first stanza adds an image of closing up, with windows shut and other people locked out. A definition, the poem suggests, is less a way of understanding than a way of building walls.
The second stanza turns from the walls to what they cost. To define is "not to look at the sky," which sets up the sky as a symbol of openness and wonder. The speaker says it ends the quest, as if curiosity stops the moment we decide we know. The last lines shift to "yourselves," addressing the reader directly, and warn that we cheat ourselves out of an infinity "that was promised." The trailing ellipsis leaves that loss hanging.
The mood is quiet but urgent, part caution and part regret. The speaker seems to want us to stay open, unfinished, and still looking up.