The word gerbil is a diminutive form of  jerboa , though the jerboas are an unrelated group of rodents occupying a similar ecological niche.
A variance is a form of equitable relief that allows a property owner to bypass local zoning laws so they can use their land in the most efficient manner possible. When unusual circumstances make it difficult for a property owner to comply with local zoning laws, cities and counties may grant what are known as variances to allow property owners to circumvent the traditional zoning laws in an area.
Variance is a measure of distribution of returns and is not neccesarily bound by any time period. Volatility is a measure of the standard deviation (square root of the variance) over a certain time interval. In finance, variance and volatility both gives you a sense of an asset's risk. If the mean is the average return of an asset, variance and volatility can give you a sense of how much that asset either overperforms or under performs.