clarus

Clarus, clara, clarum is a regular first and second declension adjective, comparative clarior, superlative clarissimus. The root idea is easy perception, and Latin applies it to two senses where English splits the vocabulary: clara lux is bright light, clara vox is a loud, carrying voice. Say "a clear voice" in English and you mean something different.

From perception it moves to reputation: a clarus vir is one everybody can see, hence distinguished. The superlative clarissimus hardened into a formal rank under the Empire, the title of senatorial men, so vir clarissimus is a job description as much as a compliment. The verb declaro, "make clear, proclaim", and the noun claritas belong to the same family, and Italian chiaro and Spanish claro carry both the brightness and the clarity straight through.