In a mental manner; an idea thought out in one's mind, as opposed to an idea spoken orally.(adverb)
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Use "mentally" in a sentence
"But McCreight's discussions with Meyer or his potential employer didn't include the term "mentally unstable," which the filing describes as "words that Mr. McCreight would never use to describe a fellow Marine.""
"I'd keep using the term mentally challenged, but "retarded" is simpler to type."
"But one of the queers - you know, what they call mentally maladjusted - might do it for fun, don't you think?"