ستردگی

thumb|Plaque in tribute to Georges Perec by [[Christophe Verdon. Café de la Mairie, Place Saint-Sulpice in Paris]] A lipogram (from , leipográmmatos, "leaving out a letter") is a kind of constrained writing or word game consisting of writing paragraphs or longer works in which a particular letter or group of letters is avoided. Extended Ancient Greek texts avoiding the letter sigma are the earliest examples of lipograms.