He was known by the name of Astika, because his father had gone away to the forest, saying 'Asti' (one is there), when he was in his mother's womb.
अस्तीत्युक्त्वा गतो यस्मात्पिता गर्भस्थमेव तम्। वनं तस्मादिदं तस्य नामास्तीकेति विश्रुतम्॥