Which literary device is used in the line an endless fountain of immortal drink?

The literary device used in the line “an endless fountain of immortal drink” is metaphor. Keats compares beauty to an “endless fountain,” implying that beauty continually nourishes and sustains the human spirit, much like a fountain provides an infinite supply of water. The phrase “immortal drink” further enhances this metaphor, suggesting that beauty is a timeless, eternal source of joy and refreshment for the soul. This image highlights the idea that beauty is not only a physical or transient experience but something that offers lasting, life-giving nourishment.

This question related to Poem 3 English Flamingo Class 12th NCERT.
From the Poem 3. A Thing of Beauty.
Give answer according to your understanding.