Etymology
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tactics (n.)
1620s, "science of arranging military forces for combat," from Modern Latin tactica (17c.), from Greek taktike techne "art of arrangement," noun use of fem. of taktikos "of or pertaining to arrangement," especially "tactics in war," adjective to taxis "arrangement, an arranging, the order or disposition of an army, battle array; order, regularity," verbal noun of tassein "arrange," from PIE root *tag- "to touch, handle."
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tactile (adj.)
1610s, "perceptible to touch," from French tactile (16c.) and directly from Latin tactilis "tangible, that may be touched," from tactus, past participle of tangere "to touch," from PIE root *tag- "to touch, handle." Meaning "of or pertaining to the sense of touch" is attested from 1650s. Related: Tactility.
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