Pipeline can mean many different things. I found these definitions that may help. A) A channel by which information passes through. B) A system through which something is conducted, especially as a means of supply. A business might talk about a future product as being in the pipeline when it will take a long time to produce. It's something that they are or are planning on working on, but haven't finished yet. Pipeline might also be referring to actual pipelines which transport oil and gas. However, there are many definitions. Knowing the type of business you're referring to will help narrow down the possibilities.