13) The skies were still blue, but a heavy cloud began to engulf George as he saw Papa coming slowly down the path. A strange feeling developed in his stomach. Now George realized what he had done. How would he face Papa? George's sensitive conscience was already hurting. In all the glory of this day, he had left a job undone and disobeyed his father. What would Papa do?
The word in this paragraph that means to swallow up is 'engulf'. In this context it means that George is overwhelmed by how he feels, his feelings of guilt are swallowing him up, they are taking over and are all he can feel. Engulf means to be completely surrounded, immersed by something that you can't control.