A History of Short Words

From the New York Times Crossword Puzzle

SSR

Sat, 23 Jul '22
20th-century map inits.
Wed, 22 Jun '22
Azerbaijan or Lithuania, once: Abbr.
Thu, 5 May '22
Kazakhstan, e.g., formerly: Abbr.
Tue, 8 Mar '22
Old atlas inits.
Sun, 15 Aug '21
Ukr. or Lith., formerly
Sun, 11 Jul '21
Tajikistan, e.g., once: Abbr.
Tue, 23 Feb '21
Map abbr. until 1991
Sun, 31 Jan '21
Union member of the 20th century, for short
Sun, 10 Jan '21
Kirghizia or Byelorussia: Abbr.