Entry 1 sense Webster, 1913 Proportionality /prəp-ôrˌ-shən-ăl'-ĭt-ē/ · Pro·por·tion·al·i·ty · IPA /pɹəpɔɹʃəˈnæləti/ 01 n. The state of being in proportion. 1. The state of being in proportion.