Sutra:
123. srI enRu periya pirAttiyArkkuth thirunAmam.

Meaning:
The divine name of Mahalakshmi is Sri.

Sri PBA Swami's Sarartha Deepikai:
The meanings of the individual terms are now beginning to be explained.

The word srI has many meanings such as wealth, etc. But, here it stands as the divine name for Mahalakshmi (periya pirAtti). The phrase "srIriti prathamam nAma lakshmyA" is to be considered here.