Sentence:  Today's wild <WSD>Mardi Gras</WSD> parades are much different than the original, more religious events of the Middle Ages. 
Meaning of the word marked with <WSD> tags:  The day, also known as Shrove Tuesday, when traditionally all fat and meat in the house were finished up, before Christians were banned from eating them during Lent, which commenced the following day on Ash Wednesday.