Basis

This is a financial term which is widely used and has many different meanings. In most circumstances, it refers to "cost" or "tax" basis, i.e. the difference between expenses and price when calculating the tax implications of a transaction.

Here's a really simple example: Vanessa buys a few shares of Flying High Medicines LLC. After any fees, expenses and her broker's hefty commission (because she decided to go the expensive route instead of trading for free through an e-brokerage), her cost basis is the leftover purchase price. This will be used to calculated capital gains or losses in the event she decides to sell her shares. If she makes a nice haul from the sale of her shares, she'll be, uh...flying high.