Avvakum (Lat.: Abacuc, Ukr.: Аввакум, Grk.: Αμβακουμ) is a biblical name derived from the name of prophet Habakuk (ca. 612 BC).
Also a notable person, protopope Avvakum Petrov (1620-1682) who led the opposition to Patriarch Nikon's reforms of the Russian Orthodox Church. Therefore, this name was popular among Old Believers (Ukr.: старообрядництво), a movement of those who also opposed the Nikonian reform.
In Ukrainian and Russian languages, this name has double "v" sound, as in
/av-va-kum/, which might lead to a misspelled "w" among the English speakers.
Volyn', Volhynya, Wołyń, and Wolynia are the various names of Volyn' region of Ukraine.
The spelling with "w" has Polish origin: Obwód wołyński.
Kovel is the second-largest city of Volyn' (ca. 69,000 population).