According to Mayo Clinic, Down syndrome causes a distinct facial appearance, intellectual disability, developmental delays, and may be associated with thyroid or heart disease in a person. So calling people with this syndrome 'Mongoloid' is extremely vulgar and disrespectful to ethnic Mongolians. Likewise, how will the population react if Down Syndrome was associated with 'European' looks? If you use this term, you are automatically a xenophobic, in my opinion.
If any difference is noteworthy, it would probably be that an age is usually between two times, e.g. 1290-1450AD, whereas an era is less set - but that isn't a rule, its just a matter of usage. Synonyms would be epoch, or eon. Source(s):
CE usually stands for  Common Era .. AD is an abbreviation for  Anno Domini  in Latin or  the year of the Lord  in English.Both measure the number of years since the approximate birthday of Yeshua of Nazareth (a.k.a. Jesus Christ) a little over two millennia ago.CE and AD have the same value.verview: CE usually stands for  Common Era .. AD is an abbreviation for  Anno Domini  in Latin or  the year of the Lord  in English. Both measure the number of years since the approximate birthday of Yeshua of Nazareth (a.k.a. Jesus Christ) a little over two millennia ago. CE and AD have the same value.