طرفاه المشبه به والمشبه
Its two terms are mushabbah bih and mushabbah.
In “al-walad ka-l-qamar fī al-jamāl”:
Mushabbah: al-walad — the boy, whose beauty is being described.
Mushabbah bih: al-qamar — the moon, whose beauty supplies the comparison.
They share a selected quality, but need not possess it equally. Often the more familiar or striking example serves as the mushabbah bih, helping the listener understand the description of the mushabbah.
These labels do not simply mirror grammatical subject and predicate; they identify the rhetorical roles of the compared terms.