overshoe
noun
over·shoe ˈō-vər-ˌshü 
: an outer shoe
especially : galosh
Example Sentences
Recent Examples on the Web Early in their development process, Mermoud, Diard, and Aubonnet considered making a downhill-only, slip-on overshoe of sorts, one that could be carried in a pack on uphill sections and attached for long, rugged downhills. 
Brian Metzler, Outside Online, 27 July 2022 Zippers was chosen in a contest in 1925 and was the brand name of a pair of rubber overshoes made by the B.F. Goodrich Co. Karen Farkas, cleveland.com, 1 May 2018
Brian Metzler, Outside Online, 27 July 2022 Zippers was chosen in a contest in 1925 and was the brand name of a pair of rubber overshoes made by the B.F. Goodrich Co. Karen Farkas, cleveland.com, 1 May 2018 Word History
First Known Use
1770, in the meaning defined above
Kids Definition
overshoe
noun
over·shoe ˈō-vər-ˌshü
: a shoe (as of rubber) worn over another for protection