Jane Odair's poem asks a question and then refuses to answer it. The speaker opens with "Love? What is love?" and spends the rest of the poem listing what love is not: not a thing, not a feeling, not physical, not mental, not permanent, not temporary. Then the poem circles back to the same question it started with.
Notice how the denials come in pairs of opposites. Physical and mental, permanent and temporary: together these seem to cover every category we might use to explain something. By ruling out both sides of each pair, the speaker suggests love slips out of every box we try to put it in. The repeated question at the end leaves us exactly where we began, which feels deliberate.
The mood is puzzled and quietly searching, but not frustrated. The short lines and plain words make it feel like someone thinking aloud, honestly admitting that love may be bigger than any definition.