FIFO

UK: /ˈfaɪfəʊ/ US: (fī′fō)

WordReference Random House Unabridged Dictionary of American English © 2025

FIFO  (fī′fō), n. 

1. Business See first-in, first-out. 
2. Computing a storage and retrieval technique, used mainly for data, in which the first item stored is also the first item retrieved.

Collins Concise English Dictionary © HarperCollins Publishers::

FIFO / ˈfaɪfəʊ/ acronym:noun

1. first in, first out (as an accounting principle in costing stock)
   Compare LIFO
2. fly-in, fly-out: referring to an employee who commutes by air to a remote location