ge·o·log·ic \|jēə|läjik, -jēk\adjective orge·o·log·i·cal\-jə̇kəl, -jēk-\ Etymology:geology + -ic, -ical : of, relating to, or based on geology : described or ascertained by geology < geologic strata > < a geologic lecture > • ge·o·log·i·cal·ly\-jə̇k(ə)lē, -jēk-, -li\adverb