FT14242 (Monk): Letters missing in this post office mail delivered around Greece (8)
A "lipogram" is a kind of constrained writing that excludes a specific letter or group of letters. The word comes from Greek: lipo (lacking) + gram (something written). A classic example is Gadsby, a 1939 novel by Ernest Vincent Wright, with over 50,000 words that do not use the letter E.
In crosswords, a lipogram is one in which the grid omits specific letter(s). A special case is the pangrammatic lipogram (or lipogrammatic pangram) – a grid that contains every letter of the alphabet except one. For example, THC11011 by Mover, with A to Y but no Z, is a pangrammatic Z-lipogram.
When uncommon letters like Q, X or Z are absent from the grid, the lipogram is probably serendipitous or an abandoned attempt at a pangram. The trick tends to catch the eye, and is likely to be deliberately done by the setter, when the excluded letter is a common one like A or E.
A more remarkable feat is to extend the lipogram to the clues in addition to the grid. An example is Afterdark's Oct 2013 puzzle THC10897, an E-lipogram that excludes the letter E entirely from the clues as well - the first recorded instance of a lipogram in The Hindu.
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