Nouns make up approximately a third of all English words; Tom, London, apple.
Abstract Nouns
Annotations:
Nouns that do not denote physical objects such as honesty and presence.
Morphological Features
Annotations:
Generally have forms that contrast one occurrence of a physical object (singular) with two or more (plural): chair, chairs / engine, engines
However there are irregularities when counting specific nouns, opposed to adding the suffix '-s' when counting more than one child, the word used is children.
Syntactic Criteria
Annotations:
When nouns combine with other words to from phrases, they most frequently combine with determiners