What does Ananta mean?

Ananta is one of the many names of Lord Vishnu and it means Limitless or Infinite.
The Shankh which represents Lord Vishnu is depicted as the ‘Jyoti’ of a mud lamp or a Diya. A simple lamp can illuminate the entire room and can lighten up numerous other lamps. In the same way, a teacher can lighten up the minds of infinite number of students with their flame of knowledge.
एक दीये से लाखों दीये |

ज्योतिषामपि तज्ज्योतिस्तमस: परमुच्यते |
ज्ञानं ज्ञेयं ज्ञानगम्यं हृदि सर्वस्य विष्ठितम् ||

He is the source of light in all luminaries, and is entirely beyond the darkness of ignorance. He is knowledge, the object of knowledge, and the goal of knowledge. He dwells within the hearts of all living beings.
Bhagavad Gita Chapter 13, Verse 18