References in classic literature ? I gave the heap a shove above the lip on the entrance. The next second there arrived up from beneath a howl of rage. encroachment, intrusion, invasion - any entry into a place not Formerly occupied; "an invasion of travellers"; "an invasion of locusts" space, https://entrance-mats82467.blogoscience.com/44353748/the-basic-principles-of-entrance-mats