Definition - What does Ishvara mean?
Ishvara is the concept of a higher power, but has different meanings, depending on the various schools of Hinduism. Ishvara is synonymous with Brahman (or Absolute Reality), but can also refer to the Supreme Consciousness or a personal god.
In yoga, many yogis choose their own ishvara to focus on in their practice.
Ishvara may be translated as "lord" in English.
Yogapedia explains Ishvara
In "The Yoga Sutras of Patanjai," the original intent of the meaning of ishvara can be interpreted in various ways. Ishvara can be theistic or non-theistic, and one may choose a known deity to meditate on (Shiva, Jesus, Buddha, etc.), or simply focus on the idea of the higher Self, higher Consciousness, life or Light.
In some Hindu schools of philosophy, it is thought that the personal god or spiritual influence of choice is understood to still be Brahman as everything is contained within the Absolute Reality.