With respect to compilation, the syntax analyzer takes the lexical units from the lexical analyzer and uses them to construct hierarchical structures called .

parse tree or parsing tree

Explanation:

A parse tree or parsing tree is an organized, rooted diagram representing a  string's lexical framework in quite a reference-free language.

They are mainly used in computer language. Parse trees represent the input  language context in practical terms,  rendering them different from conceptual syntax trees used in programming.

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