This name is descriptive of the meaning of this most ancient symbol.  This symbol goes by many names: Triskele, Trefoil, Trillium, with various spellings and pronunciations.  Though there are many concepts in ancient Celtic lore in relation to sets of three, one of the most powerful images, is the 3 phases of womanhood. The three phases, which constitute the source of life are: Maidenhood, Motherhood, and Wise Woman.  Much Honor was given to women in matriarchal celtic culture as well as pre-Druidic Neolithic tribal systems as well.  The virtuous Maiden, the nurturing Mother, and the wise Woman who has seen all 3 phases of womenhood as the giver of life. The Trinity element entwined in the center of this design is in honor of the holy trinity. This image is decidedly more in the Patriarchal realm, and I have included it here as a union of the powerful spiritual traditions that exist in Ireland and beyond.

There are other concepts worth mentioning as overlapping with this primal Spiral design, such as Life-Death_Rebirth, in the bardic tradition, the elements were Earth-Sea-and Sky. God's Goddesses, Animals and Plants often also had a 3 aspect symbolic overtone.