The crossword solution for the term 'Montenegrin Neighbor' is 'CROAT, ' which is a five-letter word. Croatia is a country located in Central and Southeast Europe, bordered by Slovenia to the northwest, Hungary to the northeast, Serbia to the east, Bosnia and Herzegovina to the southeast, and Montenegro to the south. As Montenegro's neighbor to the north, Croatia shares a long history with the country, including a period of joint rule from 1918 to 1941.