A person who carefully thinks about or examines something before making a decision.
From Latin considerare (to observe, reflect upon) + -ator (agent suffix). The root possibly derives from sidus (star), suggesting the idea of observing carefully like one observes stars.
This word is almost obsolete now, but it shows how English used to create specific job-like titles for people who did particular thinking activities — we'd just say 'someone who considers things' today!
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