Thorough, careful, or vigilant in one’s task performance; painstaking.
He was a thoughtful and conscientious worker.
Influenced by conscience; principled; governed by a strict regard to the dictates of conscience, or by the known or supposed rules of right and wrong (said of a person).
The advice of wise and conscientious people.
From Middle French conscientieux, from Medieval Latin cōnscientiōsus. Its English equivalent could possibly be analyzed as conscient + -ous. See more at conscience.
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