The ammonium ion has a formula of NH4+ and has a positive charge so it is a cation.
Meaning & History. From a Germanic name meaning eagle power, derived from the elements arn eagle and wald power. The Normans brought it to England, where it replaced the Old English cognate Earnweald.It died out as an English name after the Middle Ages, but it was revived in the 19th century.aints bearing the name include an 8th-century musician in the court of Charlemagne and an 11th-century French bishop who is the patron saint of brewers. It was also borne by Arnold of Brescia, a 12th-century Augustinian monk who rebelled against the church and was eventually hanged.
Family tree. Matthew Arnold (24 December 1822 â 15 April 1888) was an English poet and cultural critic who worked as an inspector of schools. He was the son of Thomas Arnold, the famed headmaster of Rugby School, and brother to both Tom Arnold, literary professor, and William Delafield Arnold, novelist and colonial administrator.