Potpourri is from the French word potpourri, literally ‘rotten pot’, denoting a stew made of different kinds of meat.  

The earliest recorded use of "potpourri" in English was in 1611, defined in Randle Cotgrave's "A Dictionarie of the French and English Tongues" as a Spanish dish ("olla podrida") of mixed meats stewed together. Later, in the mid-18th century, it began to be used to describe a fragrant mixture of dried flowers and spices. The first known example of this usage is in a letter from Henrietta Knight in the 1740s.  

In the early 18th century, "potpourri" also started to be used in music to describe a collection of different musical fragments.  Today, "potpourri" is commonly used to describe a fragrant mixture of dried flowers, herbs, and spices, as well as a general collection or medley of diverse items. 

Examples of potpourri used in a sentence:  
"The leaves are used in potpourri, teas, and cooking." 
"The musician played a potpourri of tunes from Gilbert and Sullivan" 
"They were at his apartment now, replaced by scented candles and bowls of potpourri." 
"Keep candles, potpourri, matches, cigarettes, etc., out of reach." 
"The room took its musky rose and aniseed scent, Banks noticed, from a bowl of potpourri on the laundry hamper under the window."