1. Toward the source or against the current
   - upstream

Antonym: downriver

• genus Balanus
• genus Balistes
• genus Ballota
• genus Balsamorhiza
• genus Bambusa
• genus Bankia
• genus Banksia
• genus Baphia
• genus Baptisia
• genus Barbarea
• genus Barosaurus
• genus Bartle-Frere
• genus Bartramia
• genus Basiliscus
• genus Bassariscus
• genus Bassia
• genus Bathyergus
• genus Batis
• genus Batrachoseps
• genus Bauhinia
• genus Beaumontia
• genus Begonia
• genus Belamcanda
• genus Bellis
• genus Bemisia