1. plural of silica; forms of silicon dioxide, a hard mineral compound found in sand, quartz, and many rocks

Examples

• Different types of silicas are used in manufacturing glass and ceramics.
• The laboratory analyzed various silicas found in the rock samples.
• Industrial silicas must meet strict purity standards for electronics production.
• Crystalline silicas can pose health risks when inhaled as dust.
• The geologist identified several silicas in the mineral collection.
• Amorphous silicas are commonly used as drying agents.