There are 2 definitions of aa in English:

aa

Syllabification: aa
Pronunciation: /ˈäˌä
 
/

noun

Geology
Basaltic lava forming very rough jagged masses with a light frothy texture. Often contrasted with pahoehoe.
More example sentences
  • Roads of black ash traverse it, winding through the otherwise untraversable aa.
  • A serpentine flow meanders through formations of smooth pahoehoe lava and rough aa lava, the same forms common in basalt lavas.
  • Very different from jagged aa, pahoehoe is the other general texture of newly solidified lava.

Origin

mid 19th century: from Hawaiian’a-'a.

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Word of the day erroneous
Pronunciation: iˈrōnēəs
adjective
wrong; incorrect

There are 2 definitions of aa in English:

AA

Syllabification: AA

abbreviation

1Alcoholics Anonymous.
1.1Antiaircraft.
1.2Administrative assistant.
1.3Associate of Arts.
1.4(Pronounced as double A) a dry cell battery size.

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