Sentence:  Halloween? I dressed up as a <WSD>Transformer</WSD>. I dressed up as a Power Ranger. I was one of the Chipmunks for God's sake. 
Meaning of the word marked with <WSD> tags:  One of the characters in the "(Transformers)" franchise who is an alien humanoid robot that can mechanically alter its appearance, or "transform", into a vehicle, creature, or (rarely) a tool.