Is it permissible to exchange verbal greetings between a man and a woman who are not mahram, without shaking hands?

It is sunnah (recommended) to greet an elderly woman or one who is not desired, and she is obligated to return the greeting. As for a young woman from whom or by whom seduction is feared, it is disliked to initiate a greeting to her or for her to return it. The Shafi'is prohibited her returning his greeting. It is permissible for a man to greet a group of women, and for men to greet a single woman when there is no fear of seduction, as was the practice of the Prophet, peace and blessings be upon him, and his Companions.