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proclivity vs. propensity

proclivity
[proh-kliv-i-tee] / proʊˈklɪv ɪ ti /

noun

proclivities plural

  1. natural or habitual inclination or tendency; propensity; predisposition.

    a proclivity to meticulousness.
    Synonyms:
    disposition, leaning, bent
    Antonyms:
    aversion
propensity
[pruh-pen-si-tee] / prəˈpɛn sɪ ti /

noun

propensities plural

  1. a natural inclination or tendency.

    a propensity to drink too much.
    Synonyms:
    proclivity, penchant, disposition, leaning, bent

  2. Obsolete. favorable disposition or partiality.