abbaco
n.— «In marked contrast to the Jesuits, Piarists taught in the vernacular, not Latin, and over philosophical mathematics they favoured “abbaco”, or mercantile arithmetic.» —“Sins of the fathers” by Miranda France Guardian (U.K.) May 22, 2004. (source: Double-Tongued Dictionary)
Further reading
There are eight major planets, but more than a million minor ones, including asteroids. If you discover one, you get the honor of naming it. The Dictionary of Minor Planet Names includes minor planets named for rock bands, jazz musicians, poets, and...
One of the celestial bodies listed in The Dictionary of Minor Planet Names(Amazon) is called Sumaura. It’s the name of the oldest private elementary school in Kobe, Japan, and was suggested by the discoverer’s son. This is part of a...