Oobleck

noun

Oo·​bleck ˈü-ˌblek 

: a mixture of corn starch and water that behaves like a liquid when at rest and like a solid when pressure is applied

A quick tap on the surface of Oobleck will make it feel hard, because it forces the cornstarch particles together. But dip your hand slowly into the mix, and see what happens—your fingers slide in as easily as through water.

—Katherine Harmon

Examples of Oobleck in a Sentence

Recent Examples on the Web

Make Homemade Goop Mix up a bowl of Oobleck, a mysterious matter that kids can shape into balls or let ooze from their fingers. — Robin Westen, Parents, 21 May 2026

Truly transformative deep tech companies are the Oobleck of the venture world. — Alexandra Vidyuk, Forbes.com, 8 Apr. 2026

This is how Oobleck, a simple mixture of cornstarch and water, works. — Rae Robertson-Anderson, The Conversation, 10 Mar. 2025

Word History

Etymology

after oobleck, a viscous green substance in the children's book Bartholomew and the Oobleck (1949) by Dr. Seuss (Theodor Seuss geisel)

First Known Use

1973, in the meaning defined above

Rhymes for Oobleck

• aztec
• breakneck
• codec
• exec
• mixtec
• paycheck
• pinchbeck
• recheck
• redneck
• toltec
• beck
• breck