Ꞩ, ꞩ, ẜ (S with oblique stroke) is an extended Latin letter that was used in Latvian orthography until 1921; ꞩ was also used in Lower Sorbian until 1950.^[1] A variant of the letter S with a stroke, ⟨s̸⟩, is used in Luiseño^[2] and Cupeño,^[3] and has been accepted for Unicode edition 16.

In Latvian orthography until 1921 it meant the sound IPA: [s] (while the S s meant the sound IPA: [z]). It was also used in the trigraph Ꞩch ẜch and the tetragraph Tẜch tẜch, denoted by the sounds IPA: [ʃ] and IPA: [t͡ʃ], respectively. Spelling reform Ꞩ ẜ ꞩ, Ꞩch ẜch, Tẜch tẜch were replaced by S s, Š š, Č č respectively.^[4]

In the final version of the Unified Northern Alphabet, created in the USSR in the 1930s for the languages of the peoples of Siberia and the Far North, for the Selkup, Khanty and Mansi languages, it meant the sound IPA: [ʃ].^[5]

The forms are represented in Unicode as:

• U+A7A8 Ꞩ LATIN CAPITAL LETTER S WITH OBLIQUE STROKE
• U+A7A9 ꞩ LATIN SMALL LETTER S WITH OBLIQUE STROKE

The long s form with the bar (diacritic) is encoded at:

• U+1E9C ẜ LATIN SMALL LETTER LONG S WITH DIAGONAL STROKE

• Latvian alphabet before 1921 (upper)
• Unified northern alphabet
• Sami alphabet. 1933 version

• Unified Northern Alphabet