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ferruginous

American  
[fuh-roo-juh-nuhs] / fəˈru dʒə nəs /

adjective

  1. Geology. iron-bearing.

    ferruginous clays.

  2. of the color of iron rust.


ferruginous British  
/ fɛˈruːdʒɪnəs /

adjective

  1. (of minerals, rocks, etc) containing iron

    a ferruginous clay

  2. rust-coloured

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of ferruginous

1655–65; < Latin ferrūginus rust-colored, derivative of ferrūgin-, stem of ferrūgō iron-rust, derivative of ferrum iron; see -ous

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Because more than 100 of the turbines, which could stand taller than the Space Needle, might pose a danger to a little-known and endangered species in the Tri-Cities area: the ferruginous hawk.

From Seattle Times • Feb. 21, 2024

The Audubon Society describes cactus ferruginous pygmy owls as hardy animals, hunting in near dawn and dusk on lizards, rodents, insects and small birds.

From Salon • Dec. 15, 2023

Others come in one of the nearly infinite shades of brown that tax the vocabulary of avian taxonomists: rufous, fulvous, ferruginous, bran-coloured, foxy.

From The Guardian • Mar. 23, 2018

Authorities say the annual Christmas Bird Count in the Twin Falls area has counted only 14 ferruginous hawks in the past 35 years.

From Washington Times • Jan. 31, 2016

Anterior wings above ferruginous; posterior rufous, with three waved bands of black, between which are imperfect oval spots.

From Zoological Illustrations, Volume III or Original Figures and Descriptions of New, Rare, or Interesting Animals by Swainson, William