numerologyPronunciation: /ˌnjuːməˈrɒlədʒi/Definition of numerology noun [mass noun] the branch of knowledge that deals with the occult significance of numbers. Derivatives numerologicalPronunciation: /-rəˈlɒdʒɪk(ə)l/ adjective numerologist noun Origin: early 20th century: from Latin numerus 'a number' + -logynumerology in other Oxford dictionaries Definition of numerology in the US English dictionary