Vinyasa Yoga means "breath synchronized movement", also called vinyasa flow because poses flow with the breath e.g. sun salutation.
It allows for a lot of variety e.g. Ashtanga and Power yoga are specialized branches of Vinyasa Yoga, with their sequences of poses. Hence Vinyasa Yoga is characterise by movement rather than stretching. Speed or alignment oriented will depend on the teacher's style, but movement is key.
If movement is for you, but the current classes are not, try different teachers and find one that suits your idea of vinyasa!
View map of yoga centres in Singapore.