ѯ

ѯ U+046F, ѯ CYRILLIC SMALL LETTER KSI ← Ѯ [U+046E] Cyrillic Ѱ → [U+0470]

English Wikipedia has an article on:

ѯ

Wikipedia

ѯ (upper case Ѯ)

1. A letter of the Cyrillic script, called ksi.

ѯ (upper case Ѯ)

1. A letter of the Old Cyrillic script, called ksi.

• 
  Regular.

ѯ • (ks) (lower case, upper case Ѯ)

1. The 45th letter of the Old Church Slavonic alphabet.

• (Old Cyrillic-script letters) А а, Б б, В в, Г г, Д д, Е е (Є є), Ж ж, Ѕ ѕ (Ꙃ ꙃ), З з (Ꙁ ꙁ), И и, І і (Ї ї), Ꙉ ꙉ, К к, Л л, М м, Н н, О о, П п, Р р, С с, Т т, Оу оу (Ꙋ ꙋ), Ф ф, Х х, Ѡ ѡ (Ѿ ѿ), Ц ц, Ч ч, Ш ш, Щ щ, Ъ ъ, Ꙑ ꙑ, Ь ь, Ѣ ѣ, Ꙗ ꙗ, Ѥ ѥ, Ю ю, Ѫ ѫ, Ѭ ѭ, Ѧ ѧ (Ꙙ ꙙ), Ѩ ѩ (Ꙝ ꙝ), Ѯ ѯ, Ѱ ѱ, Ѳ ѳ, Ѵ ѵ, Ҁ ҁ

ѯ • (ks) (lower case, upper case Ѯ)

1. A letter of the Old Novgorodian alphabet, written in the Old Cyrillic script.

Russian Wikipedia has an article on:

ѯ

Wikipedia ^ru

From the Ancient Greek letter ξ (x).

• IPA^(key): [ˈksʲi]

ѯ • (ks) (lower case, upper case Ѯ)

1. (obsolete) A letter of the Russian alphabet, called кси (ksi), and written in the Cyrillic script.