Fibonacci

British  

/ fiboˈnattʃi /

noun

1. Leonardo (leoˈnardo), also called Leonardo of Pisa . ?1170–?1250, Italian mathematician: popularized the decimal system in Europe

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Fibonacci Scientific  

/ fē′bə-nä′chē /

1. Italian mathematician who popularized the modern Arabic system of numerals in the western world and discovered the Fibonacci sequence of integers.

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Example Sentences

The next technical target sits around $5,182/oz, which represents 261.8% Fibonacci extension of the last major downswing from October, the analyst says.

From The Wall Street Journal • Jan. 26, 2026

“One of the most beautiful vegetables to grace our planet,” Selengut says of romanesco’s alien gorgeousness in her book, noting that it’s “also the mathematical nerd’s veggie of choice,” given its Fibonacci sequence formations.

From Seattle Times • Feb. 9, 2024

The philosopher typed in a program to calculate the 83rd number in the Fibonacci sequence.

From Scientific American • May 11, 2023

The 13th-century Italian Fibonacci returned from his education in North Africa armed with Hindu-Arabic numerals, liberating his fellow mathematicians and future generations from the limitations of Roman numerals and counting boards.

From Washington Post • Apr. 5, 2023

I’ve read about sea animals and honeybees, and all about a beautiful piece of math called the Fibonacci sequence.

From "The Wrong Way Home" by Kate O’Shaughnessy