useless trivia: What Word Means: Limping?

Questions

Solidified milk fat, especially cows milk, used principally as a food item?

South of Tucson, Arizona, most of the road signs are in what system?

Speaking of underwear, what does bvd stand for?

Speech disorder characterized by involuntary hesitations & rapid repetitions of speech elements (speech & speech disorders)?

Speed racer was a "demon on wheels," but what was the name of his car?