"undesirable practice"

means any act prohibited, or any failure to perform any act enjoined, by section 78(1), and, in relation to a particular bank or banks specified in a notice referred to in section 78(2)(b) or all banks, includes any act which in terms of a notice referred to in section 78(2) constitutes an undesirable practice for such particular bank, such specified banks or all banks, as the case may be;