Inflorescence
A group of flowers arranged on one stem in a set pattern.
Also: flower cluster
Many plants do not carry flowers one at a time. They group them on a shared stem, and the whole group is an inflorescence. The pattern is fixed for each kind of plant and has its own name. A foxglove carries a raceme, a lavender a spike, an onion an umbel, a lilac a panicle, and a sunflower a flower head. Grouping makes small flowers easier for pollinators to find and lets a plant open its flowers over many days.