amino

amino — adjective

  • aminopositive
  • more aminocomparative
  • most aminosuperlative

1. used to describe a chemical substance that contains a particular group of nitrog

1.adjectiveC2
Definition

used to describe a chemical substance that contains a particular group of nitrogen and hydrogen atoms (the −NH₂ group), which is the basic structural unit found in proteins.

Example

Amino acids join in long chains to build all proteins in living things.

collocation: amino acid / building blocks of proteins

The chemistry teacher showed how an amino group bonds with other atoms in a molecule.

collocation: amino group

Common collocations
  • amino acid
  • amino group
  • amino residue
  • amino compound
  • amino sequence
  • amino derivative
Synonyms
  • amine-derived

    more specific — means obtained from a particular amine compound rather than describing the general property

  • nitrogenous

    broader — means containing nitrogen in any form, not specifically the −NH₂ group

Grammar Patterns

amino + noun

Usage Note

Almost always used before a noun to describe the chemical nature of a substance. The most common use in everyday English is as part of the compound noun 'amino acid'.

Common Mistakes

This food contains many aminos.
This food contains many amino acids.
'Amino' is an adjective, not a noun; it needs a noun such as 'acid' or 'compound' after it.

Word family

  • amine
    nounC2
  • ammonia
    nounB2
  • amino acid
    nounB2
  • amino group
    nounC2

Synonym discussion

Sense: adjective/1

While 'amino' describes something that contains the −NH₂ group, 'amine' (noun) names the chemical compound that actually holds that group — you say 'an amino acid' to describe the type of acid, but 'a primary amine' to name the compound itself. 'Ammonia' (NH₃) is the simpler parent molecule from which amines are made; it is a pungent gas. 'Nitrogenous' is much broader and means 'containing nitrogen in any form' — all amino compounds are nitrogenous, but not all nitrogenous substances are amino (nitrates, for example, are nitrogenous but have no −NH₂ group). In everyday language, 'amino' appears mainly in the fixed phrase 'amino acid,' whereas 'nitrogenous' is used across many chemical contexts.

amineammonia ↗nitrogenous ↗

Common collocations

Nouns

Etymology

Ancient Greek (via Ammon)LatinFrenchEnglish

The word 'amino' was formed in the 19th century from 'amine', which comes from 'ammonia'. The name 'ammonia' traces back to Latin 'sal ammoniacus' (salt of Ammon), a substance named after the Egyptian god Ammon, because ammonium salt was found near his temple in Libya. The chemical ending '-ine' (later shortened) was added to create the class name for these nitrogen-based compounds.