Sentence:  "Tony, I'm the executive director of S.H.I.E.L.D., the Strategic Homeland Intelligence, Enforcement, and Logistics Division," explained Fury./ Tony nodded. ... "Want a tip? Fire your namer of things, because that's a <WSD>mouthful</WSD>." 
Meaning of the word marked with <WSD> tags:  Something difficult to pronounce or say.