point-blank n.

late 14c., "indicate with the finger;" c. 1400, "wound by stabbing; make pauses in reading a text; seal or fill openings or joints or between tiles," partly from Old French pointoier "to prick, stab, jab, mark," and also from point (n.).

From mid-15c. as "to stitch, mend." From late 15c. as "furnish (a garment) with tags or laces for fastening;" from late 15c. as "aim (something), direct toward an object." Related: Pointed; pointing. To point up "emphasize" is from 1934; to point out "indicate, show, make manifest" is from 1570s.

late 14c. as the name of a small French coin; 1550s as "white space in the center of a target," from the same source as blank (adj.). The meaning "empty space" (in a document, etc.) is from c. 1570. The archaic meaning "losing lottery ticket" (1560s) is behind the figurative expression draw a blank "come up with nothing" (attested by 1822).

The court has itself a bad lottery's face,

Where ten draw a blank before one draws a place;

For a ticket in law who would give you thanks!

For that wheel contains scarce any but blanks.

[from Fielding's "The Lottery," 1732]

The word has been "for decorum's sake, substituted for a word of execration" [OED] at least since 1854 (for compound words, blankety-blank), from the use of blank lines in printing to indicate where such words or the letters forming the bulk of them have been omitted. From 1896 as short for blank cartridge (itself from 1826).