The crossword solution for the term 'ER THERE!' is 'PUT'. This is a common phrase used to indicate that something should be placed in a certain location. It is often used when asking someone to PUT an item somewhere, such as 'Can you please PUT the book on the shelf?' or 'Please PUT your coat in the closet.' It is also used to suggest that someone should take action, such as 'PUT your best foot forward!' or 'PUT your thinking cap on!'