In chemistry, it means a substance that can act as either acid or base. An example is amino acids and water. See also amphiprotic.
... 1987 The Guess Who[?] 1989 The Band 1990 Maureen Forrester[?] 1991 Leonard Cohen 1992 Ian and Sylvia[?] 1993 Anne Murray 1994 Rush 1995 Buffy ...