A modification of the word "well" that expresses exasperation, frustration, and resignation. Often accompanied by a shaking of the head. The excrescent p, called a bilabial
stop, found in words like yep, and nope, is somewhat like a stifled laugh ("pfft"), a quick closing off of the word, enhancing the resignation in it, and indicating that the mouth is on its way to stating
something further. Sometimes spelled
welp.
Wellp, looks like we should start walking, this vehicle is thoroughly wrecked.
Cartoonist
Harvey Kurtzman (creator of 'MAD' magazine) used the word in a piece called "The Grasshopper and the
Ant" (Esquire - May, 1960). Ant, having just seen a caterpillar devoured by a bird says, "Wellp... Back to
work. Grain to gather."