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Synonyms

egg case

American  

noun

  1. Entomology. ootheca.

  2. Entomology. egg sac.


egg case Scientific  
  1. A protective capsule of certain animals, such as insects and mollusks, that contains eggs.

  2. See egg sac


Etymology

Origin of egg case

First recorded in 1840–50

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.

See Examples For:

No final decision has been made on the egg case.

From The Wall Street Journal Apr. 17, 2026

To capture the full picture, the research team monitored five female sharks before, during and after egg case formation.

From Science Daily Jan. 21, 2026

Battling strong currents, Ralph Pace captured this image of a swell shark egg case, revealing a glowing embryo, complete with gill slits and a yolk sac.

From BBC Oct. 14, 2025

A small hole in its base led the researchers to speculate it may be egg case or a dead sponge attachment.

From DOGO News Sep. 18, 2023

As she got closer to the thing on the wall, she saw that it was some kind of a sac, like a spider’s egg case.

From "Coraline" by Neil Gaiman

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