DOSE is an R/Bioconductor package designed for semantic similarity and enrichment analysis in the context of disease ontology (DO). It provides tools to compute semantic similarities among DO terms and genes, support hypergeometric tests, and gene set enrichment analysis (GSEA) to identify significant disease associations. The package includes several visualization functions to produce publication-quality figures, enhancing the interpretability of results. DOSE addresses the limitations of existing tools by offering customizable and accurate methods for analyzing high-throughput biological data, aiding in early diagnosis, drug repurposing, and new drug development. The package is freely available under the Artistic-2.0 License through Bioconductor.DOSE is an R/Bioconductor package designed for semantic similarity and enrichment analysis in the context of disease ontology (DO). It provides tools to compute semantic similarities among DO terms and genes, support hypergeometric tests, and gene set enrichment analysis (GSEA) to identify significant disease associations. The package includes several visualization functions to produce publication-quality figures, enhancing the interpretability of results. DOSE addresses the limitations of existing tools by offering customizable and accurate methods for analyzing high-throughput biological data, aiding in early diagnosis, drug repurposing, and new drug development. The package is freely available under the Artistic-2.0 License through Bioconductor.