The fruit developed from single ovary is called as

The fruit developed from a single ovary is called Simple fruit.
A type of fruit that develops from a single or compound ovary with only one pistil (of a single flower) is called a simple fruit. Such as Peach, tomato etc.
Simple fruits are either fleshy or dry: Fleshy fruits are those fruits in which part or all of the pericarp is fleshy at maturity.