To describe one’s work is not easily understood from the description of the term used. For "venture development" and "business development" there are as many different contexts for the tasks as people performing these tasks.
For us "venture development" is
Working with organizations to identify opportunities, create solutions, and promote success. A model for the creation and cultivation of scalable companies. It is like a puzzle with many parts that needs to be put together. The odds of success are dramatically increased in a long(er) term relationship.
For us "business development" is
The creation of long-term value for an organization: from customers to markets and relationships. In pursuit of serving the customer, new business opportunities will be identified that will result in a business growth strategy. It requires a combination of sales, marketing skills and insights, an understanding of the strategy process and awareness of technology developments.