Szarytki (read: Sha-ryt-kee) is the most popular common name of Daughters of Charity in Poland. The nickname is derived from French title: Les filles de la Charite (read: Sha-ree-te) as the first sisters came to Poland from France (sent by Vincent de Paul himslef) in 1652, the first country outside France where Daughters of Charity were sent.
There are many people, however, who think that origin of Szarytki is in their religious dress colors or style (like in France - Les Cornettes). But it is not true since the colors of Daughters of Charity is dark blue or navy blue, not gray (Szary in Polish).
Due to the role Szarytki have been playing in Poland since the very beginning of their presence there a hospital nurses are titled siostra (read: syo-st-ray), a Polish word for Sister, no matter either the nurse is lay or religious. For many decades Szarytki were organizing hospitals and ambulance care. If someone thought about nurse it must have been Daughter of Charity almost for sure.