amino acid: meaning, definition, pronunciation and examples
C1Technical / Scientific / Academic
Quick answer
What does “amino acid” mean?
One of the organic molecules that serve as the building blocks of proteins.
Audio
Pronunciation
Definition
Meaning and Definition
One of the organic molecules that serve as the building blocks of proteins.
Any of a large group of organic compounds containing both an amino group (-NH2) and a carboxyl group (-COOH). They are fundamental to all living organisms, forming the basis of proteins and playing roles in metabolism, neurotransmission, and cellular signaling.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning, spelling, or usage. The compound noun form is standard in both varieties.
Connotations
Identical scientific connotations. In everyday fitness/nutrition contexts, it carries the same associations with health, supplements, and protein synthesis.
Frequency
Equally frequent in scientific discourse. Slightly more frequent in American media due to broader commercial supplement marketing.
Grammar
How to Use “amino acid” in a Sentence
[adjective] + amino acidamino acid + [noun][verb] + amino acids[preposition] + amino acidsVocabulary
Collocations
Examples
Examples of “amino acid” in a Sentence
adjective
British English
- The amino-acid analysis was conclusive.
- We studied the amino-acid sequence.
American English
- The amino acid analysis was conclusive.
- We studied the amino acid sequence.
Usage
Meaning in Context
Business
Used in contexts of biotechnology, pharmaceuticals, and nutritional supplements (e.g., 'The new formula includes all nine essential amino acids.').
Academic
Ubiquitous in biochemistry, molecular biology, nutrition, and physiology texts (e.g., 'The polypeptide chain folds based on its amino acid sequence.').
Everyday
Common in fitness, diet, and wellness discussions (e.g., 'This protein powder has a complete amino acid profile.').
Technical
Precise usage in research, detailing specific structures, pathways, and functions (e.g., 'The enzyme catalyzes the transfer of an amino group to form the amino acid.').
Vocabulary
Synonyms of “amino acid”
Neutral
Weak
Watch out
Common Mistakes When Using “amino acid”
- Misspelling as 'aminio acid' or 'aminoaced'.
- Using it as an uncountable noun (e.g., 'The food is high in amino acid' – should be 'amino acids').
- Confusing it with 'nucleic acids' (DNA/RNA) or 'fatty acids'.
FAQ
Frequently Asked Questions
In the standard genetic code used by humans, there are 20 canonical (standard) proteinogenic amino acids. However, hundreds of other non-standard amino acids exist in nature, playing various biological roles.
Essential amino acids cannot be synthesized by the human body and must be obtained from the diet. Non-essential amino acids can be synthesized by the body from other compounds, given adequate nutrition.
No. Amino acids are the individual organic molecules. Proteins are large, complex molecules formed when many amino acids are linked together in a specific sequence and folded into a functional three-dimensional shape.
Certain amino acids, particularly the branched-chain amino acids (BCAAs), are believed to stimulate muscle protein synthesis, reduce exercise-induced muscle damage, and decrease fatigue, though the scientific evidence for benefit in well-nourished individuals is mixed.
One of the organic molecules that serve as the building blocks of proteins.
Amino acid is usually technical / scientific / academic in register.
Amino acid: in British English it is pronounced /əˌmiːnəʊ ˈæs.ɪd/, and in American English it is pronounced /əˌmiːnoʊ ˈæs.ɪd/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think: 'A-MEAN-O Acid' – It's a MEANingfully important acid for building your muscles and body.
Conceptual Metaphor
BUILDING BLOCKS (of proteins/life); ALPHABET LETTERS (that combine to form the 'words' of proteins).
Practice
Quiz
Which of the following best describes the primary role of standard amino acids?