Some types of wood are sold at a specific width and “per linear foot” of length. Lineal foot is also frequently used.
This is in contrast to “per board foot,” which is a volume measure, and can be used to tally lumber of random widths.
Example: If a 1 in. X 4 in. X 10 ft. board is priced by the linear foot, multiply the price by 10 (because the board measures 10 feet long) in order to determine the price.
See Board Foot.