amygdaloid

American  

[uh-mig-duh-loid] / əˈmɪg dəˌlɔɪd /

noun

Petrology.

1. a volcanic rock in which rounded cavities formed by the expansion of gas or steam have later become filled with deposits of various minerals.

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adjective

1. (of rocks) containing amygdules.

2. almond-shaped.

3. Anatomy. of or relating to an amygdala.

amygdaloid British  

/ əˈmɪɡdəˌlɔɪd /

noun

1. a volcanic igneous rock containing amygdales

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adjective

1. having the shape of an almond

2. a less common form of amygdaloidal

Etymology

Origin of amygdaloid

1785–95; < Latin amygdal ( a ) almond + -oid

Example Sentences

“There was one subgroup of those that had a lot of amygdaloid and cingulate cortex type of activity, so they stood out.”

From Salon • Mar. 9, 2014

The amygdaloidal masses, contained in the amygdaloid, are either entirely pistacite, or pistacite enclosing calc-spar.

From A Journey from Prince of Wales's Fort in Hudson's Bay to the Northern Ocean in the Years 1769, 1770, 1771, 1772 New Edition with Introduction, Notes, and Illustrations by Tyrrell, J. B.

It is surrounded by pyroxenic amygdaloid; it would no doubt be seen below, issuing immediately from gneiss-granite, like the phonolite of Biliner Stein, in Bohemia, which contains fragments of gneiss embedded in its mass.

From Personal Narrative of Travels to the Equinoctial Regions of America, During the Year 1799-1804 — Volume 3 by Humboldt, Alexander von

It rings upon rocks of amygdaloid and porphyry.

From The Rifle Rangers by Reid, Mayne

Among the relics of their occupation I picked up, here, an unusually fine implement of the "amygdaloid" shape.

From Fountains in the Sand Rambles Among the Oases of Tunisia by Douglas, Norman