| ̷ ̷ ̷ ̷ˌ ̷ ̷+...- noun
Etymology: International Scientific Vocabulary naphthalene + sulfonic
1. : either of two crystalline monosulfonic acids C 10 H 7 SO 3 H obtained by sulfonation of naphthalene and used in the synthesis of dyes and naphthols
2. : any of numerous sulfonic acids derived from naphthalene