What is the meaning of ʹ?

A mark used for transliteration of Cyrillic Ь.

A mark for palatalization in Cyrillic dictionaries, equivalent to IPA ʲ.

Alternative form of (stress mark).

The twenty-ninth letter of the Ludian alphabet, called pehmed pilkeh and written in the Latin script.

Suprasegmental palatalization is marked by a free-standing prime or acute accent (´) added after the vowel.

The twenty-ninth letter of the Veps alphabet, called pehmenduzznam and written in the Latin script.

Source: wiktionary.org