The Web of Things (WoT) uses Web technologies to engage connected objects in applications. However, building context-aware WoT applications requires accurate context description. In this paper, we overview different context modeling approaches in various fields related to the WoT, before studying the architecture of WoT applications. Based on our study, we propose a multi-level and multi-dimensional context meta-model to help identify and organize context information WoT applications need to deal with adaptation.