Slavic honorifics
Speakers of Slavic languages and Lithuanians (Baltic languages) use two main sets of honorifics. West Slavs and Ukrainians use the title Pan, South Slavs and Russians use Gospodin, while Belarusians use either Pan or Spadar, and Lithuanians use either Ponas or Gaspadorius.
Usage of Pan
Pan is used to varying degrees in a number of countries – Poland, the Czech Republic, Slovakia, Ukraine, Belarus and Lithuania (Ponas). Historically, Pan was equivalent to "Lord" or "Master" (ruler, suzerain).
Pan is most common in Poland. The feminine form is Pani and the collective is Państwo. Panna is sometimes used to refer to young women but is becoming less common. The use of Pan differs significantly from English honorifics. It is used as an honorific (roughly equivalent to Mr) before the name (first name and surname, only surname, or only first name) and as a form of address without the name (roughly equivalent to "Sir").
Use of Pan with the first name in Poland marks a combination of familiarity and respect. Unlike "Sir", Pan is used both ways between persons of both equal and unequal rank (a waiter will address a guest as Pan, and the customer reciprocates, much like using Monsieur in French). Using Pan with only the first name is regarded as a disrespectful way of addressing people, even somewhat condescending, when it is used to a superior. Using Pan with only the surname, however, is normally respectful if talking about somebody. Pan is never used about oneself (unlike "Mr").
"Pan" is also used as a kind of personal pronoun in a similar way as Usted in Spanish or Lei in Italian (unlike French 'Monsieur' or German 'Herr', which require the use of 'vous' and 'Sie' respectively). A non-Slavic language, Lithuanian, has a similar title, Ponas.
Other titles
Spadar appears in Belarusian. It is a simplified version of Haspadar, which is related to Gospodin or the Slovene Gospodar. Gaspadorius and gaspadinė for a women appears in Lithuanian language. It is an archaic word and it is not used today in the general language, however it is not extinct and sometimes used in a countryside. It originated from Proto-Slavic, ultimately from *gospodь, compare Bulgarian, Serbo-Croatian and Ukrainian господар (hospodar), which means householder, master of the house or head of a household.
Vladyka (literally, ruler/master), is used when referring to a bishop or patriarch in Eastern Orthodox churches.
Sudar, appearing without a personal name, was formerly used in Russian. It may be connected to the Russian title of a head of state, Gosudar. Its Ukrainian counterpart was (Pane) Dobrodeeyu or (Pani) Dobrodiyko (pl. Dobrodeeyi). Those titles became obsolete and are now found only in novels. Appeal of Shanovni Dobrodeeyi ("Dear Goodwill") is still used solemnly to many people.
In Ukrainian, Panych was once used to refer to noble youngsters and generally referred to the Polish people. It is spelled Panicz in Polish.
Under communism
The equivalent of Comrade replaced most titles in the Communist-era Eastern bloc, except Poland.
In Poland, Obywatel ("citizen") replaced Pan, which was restored after the fall of Communism. The word "citizen" was chosen for ideological reasons as pan (sir) was historically a title of a nobleman. The equivalent of Russian comrade – towarzysz – was a title reserved only for communist party members.