The quality or state of being constrained; the feeling of being restricted, limited, or uncomfortable.
From constrained plus the noun-forming suffix -ness. This abstract noun transforms the adjective into a concept you can discuss—the actual sensation or quality of being held back.
Medieval philosophers loved talking about 'constrainedness' as they debated whether humans had free will or were constrained by God's plan—it's basically a fancy way to discuss feeling trapped.
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