* Two cotyledons: The seed contains two seed leaves (cotyledons) that provide food for the developing embryo. This is a defining feature of dicots.

* Netted leaf venation: The veins in the leaves form a network pattern, characteristic of dicots.

* Taproot system: The main root, called the taproot, grows straight down and branches out, unlike the fibrous root system found in monocots.

* Floral parts in multiples of four or five: The flowers of winged bean have petals and other parts arranged in multiples of four or five.

These characteristics clearly place winged bean in the dicot group, unlike monocots which have a single cotyledon, parallel leaf venation, fibrous root system, and floral parts in multiples of three.