The antonyms for the word "turns upsidedown" include stabilizes, secures, solidifies, unifies, and organizes. These words represent the opposite action or effect of "turning upside down." Stabilizing indicates the act of making something firm, secure, or stable; securing means to fasten or make something safe and dependable; solidifying suggests making something more fixed, clear, and distinct; unifying relates to bringing something together, integrating, or consolidating; and organizing means establishing a system or order. In contrast to "turning upside down," these antonyms suggest the idea of structure, management, and consistency.