diamondback

American  

[dahy-muhnd-bak, dahy-uh-] / ˈdaɪ məndˌbæk, ˈdaɪ ə- /

adjective

1. bearing diamond-shaped marks, designs, or configurations on the back.

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noun

1. diamondback rattlesnake.

2. diamondback terrapin.

3. diamondback moth.

diamondback British  

/ ˈdaɪəməndˌbæk /

noun

1. Also called: diamondback terrapin.   diamondback turtle.  any edible North American terrapin of the genus Malaclemys, esp M. terrapin, occurring in brackish and tidal waters and having diamond-shaped markings on the shell: family Emydidae

2. a large North American rattlesnake, Crotalus adamanteus, having cream-and-grey diamond-shaped markings

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Etymology

Origin of diamondback

First recorded in 1810–20; diamond + back ¹

Example Sentences

Seven native rattlesnake species are in California, including the Mojave, Western diamondback, red diamond, Southern Pacific, Northern Pacific, Great Basin, and the speckled rattlesnake.

From Los Angeles Times • Mar. 23, 2026

It turned out to be a diamondback terrapin.

From The Wall Street Journal • Oct. 30, 2025

The woman placed a box next to the home’s front door Monday evening when the eastern diamondback snake jumped out and bit her, the Martin County Sheriff’s Office said in a news release.

From Seattle Times • Sep. 19, 2023

Researchers subjected the skeletal remains of pond sliders, diamondback terrapins, painted turtles and box turtles to incremental increases in mechanical forces and measured where and how the shells began to buckle.

From New York Times • Dec. 26, 2022

It had the head of a lion with a blood-caked mane, the body and hooves of a giant goat, and a serpent for a tail, a ten-foot-long diamondback growing right out of its shaggy behind.

From "The Lightning Thief" by Rick Riordan