Dictionaries can be either descriptive or translation dictionaries. The Library also has several specialized dictionaries focused on a particular field. Translations can be found in MOT Dictionaries.
A thesaurus is a controlled vocabulary that gathers and connects related concepts. For example, Finto is a Finnish thesaurus and ontology service with multiple subject-specific vocabularies.
Reference works can be general or subject-specific: encyclopedias and handbooks act as systematic introductions to a particular field or topic, and they tend to contain concise basic information.