Virtual reality (VR) technologies have huge potential to enable radically new applications, among which spherical panoramic (a.k.a., 360°) video streaming is on the verge of hitting the critical mass. Current VR systems treat 360° VR content as plain RGB pixels, similar to conventional planar frames, resulting in significant waste in data transfer and client-side processing. In this paper, we make the case that next-generation VR platforms can take advantage of semantics information inherent to VR content so as to improve the streaming and processing efficiency. To that end, we present SVR, a semantic-aware VR system that utilizes the object information in VR frames for content indexing and streaming. SVR exploits the key observation that end-users' viewing behaviors tend to be object-oriented. Instead of streaming entire frames, SVR delivers miniature frames that cover only the tracked visual objects in VR videos. We implement SVR prototype with a real hardware board and demonstrate that it achieves up to 34% network bandwidth reduction along with 21% device power saving.