Diversity refers to racial, religious, cultural, and other "diversity" being increasingly promoted within a single society. Racial diversity is the blending of many ethnic backgrounds, and is used to justify the practice of affirmative action. "Diversity" is also used as an excuse for the promotion or toleration of abnormal sexual practices, and for the redefinition of marriage away from the traditional definition of one man, one woman. "Diversity hiring" is a currently fashionable business buzzword.
Species Diversity in Permaculture
In permaculture gardening-farming, there is the core concept of polyculture - a technique of agricultural diversity or ecodiversity. Polyculture is agriculture using multiple crops and/or animals in the same space. This is done as an imitation of the biodiversity of natural ecosystems. In nature large stands of single crops, known as monoculture rarely exist. Intercropping and companion planting are like "polyculture lite". They use 2 or 3 plants planted together while polyculture can use up to 10 or 20 plants in the same area. Polyculture is not limited to just plants. It can be used to describe systems using multiple animals as well. Joel Salatin of PolyFace Farms use a rotational grazing systems of cows, chickens, pigs, and rabbits in a polyculture. 
- Diversification, i.e., of investments beyond just a stock portfolio - see Invest in tangibles