sedulous

The word 'sedulous' originates from the Latin adjective sedulus, meaning "diligent" or "painstaking." While its ultimate origin is uncertain, it is traditionally thought to derive from se dolo, meaning "without guile," suggesting a sense of earnest, straightforward application. This Latin root passed into English in the mid-16th century, retaining its core meaning of persistent and careful effort. The suffix '-ous' is a common adjectival ending in English, ultimately from Latin, used to denote a possessing or full quality, thus forming a word that characterizes someone as being full of diligence.

Structure: sedul (diligent) + ous (adjective suffix) - sedul: From Latin sedulus, meaning "diligent, zealous, painstaking." - ous: An English suffix forming adjectives, from Latin -osus, meaning "full of, characterized by."