Third-person singular simple present indicative form of understand.(verb)
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Use "understandeth" in a sentence
"[11] There is none that understandeth, there is none that seeketh after God."
"'She knoweth and understandeth all things, and she shall lead me soberly in my doings, and preserve me in her power ... and then shall I judge thy people righteously.'"
"Said the slave, ‘O my lord, wilt thou go in to one who understandeth or to one who understandeth not?’"