Fibonacci numbers

[ fee-boh-nah-chee ]

plural noun

, Mathematics.

1. the unending sequence 1, 1, 2, 3, 5, 8, 13, 21, 34, … where each term is defined as the sum of its two predecessors.

Word History and Origins

Origin of Fibonacci numbers¹

1890–95; after Leonardo Fibonacci, 13th-century Italian mathematician