sibylline

[ sib-uh-leen, -lahyn, -lin ]
/ ˈsɪb əˌlin, -ˌlaɪn, -lɪn /

adjective

of, resembling, or characteristic of a sibyl; prophetic; oracular.
mysterious; cryptic.
Also si·byl·ic, si·byl·lic [si-bil-ik] /sɪˈbɪl ɪk/.

Origin of sibylline

First recorded in 1570–80, sibylline is from the Latin word Sibyllīnus pertaining to a sibyl. See sibyl, -ine1
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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