rho·do·bac·te·ri·a·ce·ae \|rō(ˌ)dō(ˌ)bakˌtirēˈāsēˌē\noun plural Usage: capitalized Etymology: New Latin, from Rhodobacterium, type genus (from rhod- + Bacterium) + -aceae in some classifications: a family of Thiobacteriales coextensive with Rhodobacteriinae