I'm not sure what to use. We use wait for her to stay at the bottom/top of stairs and when we go through the doorways. In the next training class I know Hold is for putting something in their mouth and holding it.... ???
Are you looking for a command to use? What about "steady" or "keep" or "patience"? It can be whatever you want really; it can be gibberish, as long as you remember to use it consistently.