When you despise /dɪˈspaɪz/ (dis-paayz) something, you find it despicable, which is pronounced as /dɪˈspɪkəbəl/ (dis-pik-ə-bl) for some reason, rarely also /ˈdɛspɪkəbəl/ (des-pik-ə-bl). The word “despisable” /dɪˈspaɪzəbəl/ (dis-paay-zə-bl) (spelled with an “s”) theoretically exists in some dictionaries, but no-one really uses it in practice.
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