This word is from the Spanish tesauro.
A thesaurus is a book that lists words in groups of synonyms and related concepts.
A dictionary focuses on definitions of a word, while a thesaurus focuses on providing single-word synonyms for a particular word.
Ang diksiyonaryo ay nagbibigay ng depinisyon para sa bawat salita, habang ang tesawro naman ay naglilista ng mga kasingkahulugang salita.
For example, an entry in a dictionary could be like this:
machine – an apparatus consisting of interrelated parts with separate functions, used in the performance of some kind of work
An entry in the thesaurus could be as follows:
machine – apparatus, appliance, automobile, gadget, instrument, motor, vehicle, automaton, implement, mechanism