Lewisian
Adjective
Meaning
Of or relating to C. S. Lewis (1898–1963), writer and theologian, known for the children's fantasy series The Chronicles of Narnia and for non-fictional Christian apologetics.
Of or relating to Clarence Irving Lewis (1883–1964), American academic philosopher and the founder of conceptual pragmatism.
Of or relating to David Lewis (1941–2001), American philosopher.
Source: en.wiktionary.orgExamples
Birlinn. p. 93 state of the Lewisian gneiss bedrock of much of the Outer Hebrides that "these rocks are amongst the oldest to be found anywhere on the planet".
Smaller formations of Lewisian gneiss in the northwest are up to 3 billion years old.