of, relating to, or belonging to the Umbelliferae, a family of herbaceous plants and shrubs, typically having hollow stems, divided or compound leaves, and flowers in umbels: includes fennel, dill, parsley, carrot, celery, and parsnip
2.
designating any other plant bearing umbels
[C17: from New Latin umbellifer, from Latin umbella sunshade + ferre to bear]