What,for you,is the significance of the title of 'An Ideal Husband' ?

The significance of the title is that there are no "ideal husbands." An ideal husband simply doesn't exist, and women always seem to idealize what their husbands are not.

There are no ideal husbands! As the book suggest the man loved his wife but he was keeping a secret from her.

No one is "ideal" in the end because Sir Robert Chiltern lied to his wife who idealised him so much! but is Lady Chiltern ideal? She isn't either because being a wife she should understand and accept her husband's qualities and imperfections as stated in the play. The title in itself is an ironic one since in the end no one is ideal.