One of the names of God Śiva (Siva), mentioned in Śivasahasranāmastotra. Nīlakaṇṭha (Nilakantha), the commentator, while clarifying the meaning of the name ‘Ādikara’, has said —
In one of the mantras in Ṛgveda (Rigveda) it is said that, in the beginning of creation, there had been only Hiraṇyagarbha. He is the creator and ruler of all the universe, he had placed the ether and the earth in their own location–
Hiraṇyagarbhaḥ samavartatāgre bhuvasya jāta patireka āsīt
sa dādhāra pṛthivīṁ dyāmutemāṁ kasmai devāya haviṣā vidhema.
Sāyanācārya (Sayanacharya), the commentator of Ṛgveda (Rigveda), has said — the Creator of all the universe, the Prajāpati (Prajapati; Ruler of the People) who holds the whole universe like a golden egg inside his own ‘womb’ or genital organ , is known as Hiraṇyagarbha (Hiranyagarbha; One with the golden womb) —
hiraṇmayāsyāṇḍasya garbhabhūtaḥ prajāpatirhiraṇyagarbaḥ.
Accoring to the conception of Purāṇa, Hiraṇyagarbha and Prajāpati (Prajapati) Brahmā (Brahma) are One and the same. And according to Upaniṣad (Upanishad), when the static , formless Brahman conceptualises the creation of the universe, Hiraṇyagarbha emerges from that formless Absolute Reality, in order to create the universe. God Śiva (Siva) is imagined to be the manifestation of that Brahman, who is the creator of Hiraṇyagarbha. So he is addressed as Ādikara (Adikara). From this idea, he is also known as Ādyanirgama (Adyanirgama).