"Obstreosis of the ductal tract. Tertiary. Wish you'd take a look at him." "Glad to," said Mitty. (5)
Mitty even makes up words and terms in his imaginings – his dreams always have the tinge of kid-like fantasy.
Walter Mitty took the gun and examined it expertly. "This is my Webley-Vickers 50.80," he said calmly. (10)
This is an absurdly large gun, of course – again we see that Walter's fantasies are absurd; he doesn't know much about the lifestyles he pretends to live.