gymslip (?d??m?sl?p) n (Clothing & Fashion) a tunic or pinafore dress worn by schoolgirls, often part of a school uniformCollins English Dictionary ? Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014