Generate an overlapping word between the given two sentences. When you find the overlapping words, they don't have to match exactly, e.g., "survival" and "survive" are valid overlapping words. Little words like "the" or "of" don't count! You must generate significant words which are not the stop words.

Q: Sentence1: smell is used for finding food by some animals. 
Sentence2: Food includes small rodents and birds.

A: food
****
Q: Sentence1: Dams are very damaging to rivers. 
Sentence2: Creating a lake can be very damaging to rivers.

A: damaging
****
Q: Sentence1: Bioterrorism is another potential threat in the environment. 
Sentence2: Education is the Key to Defense Against Bioterrorism.

A:
Bioterrorism
****