from The American Heritage® Dictionary of the English Language, 4th Edition

  • n. A small gas bubble in igneous, especially volcanic, rock filled with secondary minerals such as zeolite, calcite, or quartz.

from Wiktionary, Creative Commons Attribution/Share-Alike License

  • n. A rounded mass of secondary mineral found in volcanic rock

from The Century Dictionary and Cyclopedia

  • n. One of the crystalline nodules found in amygdaloid (which see).


Latin amygdala, almond (from its shape); see amygdala + (nod)ule.
(American Heritage® Dictionary of the English Language, Fourth Edition)


Sorry, no example sentences found.


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