Monoecious Angiosperms : Plants bear both male and female unisexual flowers on the same plant. e.g. Cucurbits / coconut / maize.
Dioecious Angiosperms : Plants bear either male or female unisexual flowers on different plants. e.g. Papaya / date palms.
Detailed Answer :
Angiosperms bearing unisexual flowers can be dioecious if male and female flowers occur on separate plants. e.g., in date palm and papaya. However, in Cucurbita, plants bear unisexual male and female flowers which are present on same parent plant. Hence, it is monoecious.
