expression
without eating or drinking
Describes a state of having had nothing to eat or drink, often for a long period. Frequently used with で to indicate the condition under which an action is performed.
彼は飲まず食わずで三日間も働き続けた。
He kept working for three days without eating or drinking.
遭難者は飲まず
The stranded person waited for rescue without food or water.