There's a reason it sounds like Chaplain...it is believed to originate from the Latin term, capellanus or cappellanus, an office given to persons appointed to watch over the sacred cloak (cappa or capella) of St. Martin of Tours. The surname is common among Ashkenazi Jews, usually indicating descent from the priestly lineage (the kohanim), similar to the etymological origin of the surname Cohen.
A user entered the following on the page in 2012. This doesn't seem to be the place for it. I'll keep it in case they need the information: Rabbi Pinchas Kaplanof Baranovitch. Father of Ester Zisking, who married Rabbi Zvi Menachem Zisling.