gunwalePronunciation: /ˈgʌn(ə)l/ (also gunnel)Definition of gunwale noun (often gunwales) the upper edge or planking of the side of a boat or ship. Phrases to the gunwales informal so as to be almost overflowing:the car is stuffed to the gunwales with camera equipmentOrigin: late Middle English: from gun + wale (because it was formerly used to support guns)gunwale in other Oxford dictionaries Definition of gunwale in the US English dictionary