– **Characteristics of Aggregate Fruit:**
– Develops from merger of several ovaries in one flower
– Contrasted with simple fruit (from one ovary) and multiple fruit (from multiple flowers)
– Terminology reversal by John Lindley affects English vs. other languages
– Not all flowers with multiple ovaries form aggregate fruit
– Aggregate fruits can also be accessory fruits
– **Examples of Aggregate Fruit Parts:**
– Drupelets: Raspberry, Dewberry, Blackberry
– Achenes: Strawberry, Ranunculus
– Follicles: Magnolia
– Samaras: Liriodendron tulipifera
– Sugar apple fruit formed from pistils and receptacle of one flower
– **Components of Sugar Apple Fruit:**
– Made up of individual berry-like pistils fused with receptacle
– Example of more complex aggregate fruit structure
– Difficult to define components compared to other aggregate fruits
– **Related Concepts:**
– Multiple fruit: Formed from ovaries of several flowers
– Compound fruit: Term for uncertain fruit type (aggregate, multiple, or simple)
– Accessory fruit: Flesh derived from tissue exterior to the carpel
– Carpel: Building blocks of the ovary
– **References:**
– Define Etaerio at Dictionary.com
– “The Cambridge Illustrated Glossary of Botanical Terms” by M. Hickey & C. King (2001)
– “Confusion between multiple and aggregate fruits” by R. Spjut & J. Thieret (1989)
– “The Kew Plant Glossary: an Illustrated Dictionary of Plant Terms” by H. Beentje & J. Williamson (2010)
– “The Encyclopedia of Fruit and Nuts” by J. Janick & R.E. Paull (2008)
An aggregate fruit or etaerio (/ɛˈtɪərioʊ/) is a fruit that develops from the merger of several ovaries that were separated in a single flower. In contrast, a simple fruit develops from one ovary, and a multiple fruit develops from multiple flowers. In languages other than English, the meanings of "aggregate" and "multiple" fruit are reversed, so that "aggregate" fruits merge several flowers. The differences in meaning are due to a reversal in the terminology by John Lindley, which has been followed by most English-language authors.

Not all flowers with multiple ovaries form aggregate fruit; the ovaries of some flowers do not become tightly joined to make a larger fruit. As a result, many fruits form which are commonly mistaken to be of the aggregate variety. Aggregate fruits may also be accessory fruits, in which parts of the flower other than the ovary become fleshy and form part of the fruit.
The individual parts of an aggregate fruit come in many forms. Common examples are:
- Drupelets:
- Raspberry
- Dewberry and blackberry, also an accessory fruit, with a fleshy receptacle
- Achenes:
- Strawberry, also an accessory fruit, with a fleshy receptacle
- Ranunculus
- Follicles:
- Samaras:
The components of other aggregate fruit are more difficult to define. For example, sugar apple (Annona spp.) fruit are made up of individual berry-like pistils fused with the receptacle.