Senseless

wiktionary

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From sense +‎ -less. Compare Saterland Frisian sinloos(“senseless, foolish”).

etymonline

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senseless (adj.)

1550s, "without sensation," from sense (n.) + -less. Of actions, etc., "devoid of purpose, proceeding from lack of intelligence," it is attested from 1570s. Related: Senselessly; senselessness.