basic subgroup
subgroup of an abelian group which is a direct sum of cyclic subgroups and satisfies further technical conditions
en-GB/ˈbeɪsɪk ˈsʌbɡɹuːp/
en-US/ˈbeɪsɪk ˈsʌbˌɡɹup/
subgroup of an abelian group which is a direct sum of cyclic subgroups and satisfies further technical conditions