[{"Bold_text": "adjective", "List Items": ["Chemistry.having a valence of two.having two valences, as aluminum with valences of two and three.", "having a valence of two.", "having two valences, as aluminum with valences of two and three.", "Genetics.pertaining to associations of two homologous chromosomes."]}, {"Bold_text": "noun", "List Items": ["Genetics.a pair of bivalent chromosomes, especially when pairing during meiosis."]}]