Left element formerly contained three, many「orifices, mouths」now expressed as「restricted」with「deficient, lacking, missing parts, headless, gaping open.」As「zone owing, deficient」may have referred to the huge debt owed by Europeans to China a few hundred years ago, especially the English who later attempted to mitigate their debtor position somewhat by pushing opium in China and addicting the nation.
Today meaning EUROPE as a「zone」of many small, contained countries that is「gaping open」that perhaps refers to possible access from many directions, or to the Mediterranean Sea, Baltic Sea, North Sea, Black Sea, Caspian Sea, Norwegian Sea, Barents Sea, Atlantic Ocean, and so on.
Some have suggested the「many orifices」element as various languages, but most continents also have many, so it is likely that the Chinese had a different intent in mind, with Europeans not being as adept or as well-trained with regard to the many uses of orifices:「red zone deficient.」May well have depicted the surprise that the first Europeans who visited China expressed when first seeing Chinese red zones where the brothels and service providers labored,「in the red zone with wide open and gaping-mouth surprise」or,「losing one's head with hookers.」Replacement glyph depicts the district where the singing girls could be rented on a short-term basis,「zone of intercourse, sexplay.」Perhaps Europeans in China often could be found visiting the districts where the singing girls plied their trade, equipped with skills unknown to Europeans at that time.
Still others say these elements refer to the「delicate zone beheaded」of circumcised missionaries from Europe. Circumcision has been religious dogma of Islam, Judaism, and some Christian religions for centuries…January 1 is the Christian Feast of the Circumcision. Note that none of these religions originated with the Chinese, and that circumcision has never really quite caught on as being popular in east Asia, to date.

External source definitions …excluding politically incorrect concepts and other meanings deemed offensive today; may include extended definitions, euphemisms, and mnemonics)
Chinese: old variant of 謳|讴; Europe
Japanese EDRDG: Europe
Unihan extended: translit.: Europe; ohm

Used within names (nanori)
おお　･　ひろ