ABC

n. alphabet; fundamentals, basics

based on nuclear bacterial or chemical methods (of weapons)

ABC are the first three letters in the Latin alphabet. ABC may also refer to the phrase "as easy as ABC", that is something that is fundamentally simple and easy.
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Noun
1. the elementary stages of any subject (usually plural); "he mastered only the rudiments of geometry"
(synonym) rudiment, first rudiment, first principle, alphabet, ABC's, ABCs
(hypernym) fundamentals, basics, fundamental principle, basic principle, bedrock
(classification) plural, plural form

n. Abc, alphabet; fundamentals, basics

n. alphabet, Abc; series of letters used in a certain language; fundamentals, basics