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From our dictionary:
pic•a•yune

(pik"E•yOOn', pik"u-), adj. Also,pic"a•yun'ish. Informal.
1. of little value or account; small; trifling: a picayune amount.
2. petty, carping, or prejudiced: I didn't want to seem picayune by criticizing.n.
1. (formerly, in Louisiana, Florida, etc.) a coin equal to half a Spanish real.
2. any small coin, as a five-cent piece.
3. Informal.an insignificant person or thing.

Pic•a•yune

(pik"u•yOOn', pik"E-), n.
a town in SE Mississippi. 10,361.