From Longman Business Dictionarylast in, first outlast ˌin, first ˈout abbreviation LIFO noun [uncountable]1ACCOUNTING a method of calculating the value of goods or materials held in stock, based on the principle that those put in stock last are the first ones sold or used. Any stock that is left at the end of the year is valued at the cost of the first goods boughtStocks were valued according to the last in, first out principle. → compare first in, first out2HUMAN RESOURCES a system used by companies who are reducing the number of people working for them, in which the people who joined the company most recently lose their jobs firstThe company were firing people on the last in, first out basis.