Phase door - an entrance towards the backstage location of theater; used by performers together with other theater staff encroachment, intrusion, invasion - any entry into an area not Earlier occupied; "an invasion of travelers"; "an invasion of locusts" maintain - keep the attention of; "The soprano held the audience"; https://entrance-mats24556.liberty-blog.com/38025442/the-fact-about-entrance-mats-that-no-one-is-suggesting