There's biannual/biennial: think quick, which means twice a year and which means every two years? http://en.wiktionary.org/wiki/biannual http://en.wiktionary.o

There's biannual/biennial: think quick, which means twice a year and which means every two years? http://en.wiktionary.org/wiki/biannual http://en.wiktionary.org/wiki/biannual / http://en.wiktionary.org/wiki/biennial http://en.wiktionary.org/wiki/biennial