get the measure of

get the measure of (someone or something)

To understand or know someone or something well and use that knowledge accordingly; to have an accurate conception of someone or something. I've gotten the measure of the students, and I just don't think that topic will hold their interest at an assembly.
See also: get, measure, of

get (or take or have) the measure of

assess or have assessed the character, nature, or abilities of someone or something.
See also: get, measure, of

get/have/take the ˈmeasure of somebody

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get/have/take somebody’s ˈmeasure

(formal) form an opinion about somebody’s character or abilities so that you can deal with them: The champion soon had the measure of his young opponent.
See also: get, have, measure, of, somebody, take