Widely used as a purple dye in textiles and paper industries due to its strong color and affinity for cellulose-based materials. Commonly employed in microscopy as a staining agent to visualize cell structures, particularly in Gram staining where it differentiates bacterial types. Used in veterinary medicine as a topical antiseptic and antifungal agent for fish and aquatic species, especially in treating fungal infections in fish eggs and skin. Applied in some diagnostic procedures and biological assays as a pH indicator and colorimetric reagent. Historically used in ink formulations for writing and printing, known for producing permanent, water-resistant marks. Also utilized in some research settings as a photosensitizer in photodynamic therapy studies and as a model compound in environmental degradation experiments.