Wikipedia
A Towarzysz ("Companion", plural: towarzysze) was sort of a junior cavalry officer or rather knight-officer in the autorament narodowy Polish-Lithuanian Commonwealth National army, both in cavalry and infantry, from the 16th century until 1794 AD.
During the 19th century Towarzysz assumed the same meaning as the Russian communist товарищ (tovarishch), or ' comrade' in English language, and as such was used in the 20th century and today, with the military meaning fading in use. Use of expressions such as "Pan" ("Sir") was frowned upon and the communist government encouraged use of "Towarszysz" (comrade) or "Obywatel" (Citizen).
In the Polish-Lithuanian Commonwealth's National army (until the 1775 AD reforms) towarzysz was usually a noble who served for a period of time (usually less than 5 years) in the Army as a horseman with his mounted retainers (cavalry) and free servants ( hussars, cossack – pancerny, petyhorcy, haiduk), or with none or one retainer and very few free servants (light cavalry e.g. Wallachian, lisowczyk, Tatar), organized into banners/companies ( chorągiew). His pay was relative to the type of cavalry unit he served, whether in ( hussars, cossack – pancerny), banners. He usually brought between 1 and 4 men ( pocztowy or pacholiks) with him in his "retinue" ( poczet) prescribed by his current military contract with his commander, the rotameister ( rotmistrz), and the state. He armed, provisioned and commanded his retainers, and his free servants, that provided care for horses and weapons, forage, set up camp, and mended equipment. In the light cavalry, a towarzysz usually fought with a very small poczet.
They were differentiated based on their horse unit origin, depending on whether they joined a heavy cavalry unit – (Towarzysz husarski of the Polish hussars), a medium cavalry banner – towarzysz kozacki (name change after 1648 AD – Towarzysz pancerny), a light cavalry banner – towarzysz lekkiego znaku etc. The richest and most prestigious were towarzysze that came from the winged hussar banners, but their own expenses' burden was the most excessive and grew as the 17th century progressed. After 1775 reforms that modernized Polish-Lithuanian cavalry towarzysz was usually a lancer and a head of the smallest unit in the Kawaleria Narodowa, Pulk Jazdy Przedniej or other various guard cavalry regiments of the Commonwealth.