"destroy, eradicate," 1530s, from Latin deletus, past participle of delere "destroy, blot out, efface," from delevi, originally perfective tense of delinere "to daub, erase by smudging" (as of the wax on a writing table), from de "from, away" (see de-) + linere "to smear, wipe," from PIE root *(s)lei- "slime, slimy, sticky" (see slime (n.)). In English, specifically in reference to written matter from c. 1600. Related: Deleted; deleting.
1580s, "a word or passage deleted;" c. 1600. "act of blotting out or erasing," from Latin deletionem (nominative deletio), noun of action from past-participle stem of delere "destroy, blot out, efface" (see delete).
"take out, remove," typographer's direction to remove a letter, 1727, ultimately from Latin delere "destroy, blot out, efface" (see delete), perhaps via dele, imperative singular, or deleatur "let it be deleted," third person singular present passive subjunctive (which itself was used in English from c. 1600). Usually expressed by a distinctive script form of "d".