What is the meaning of Grotto?
A small cave.
An artificial cavern-like retreat.
A Marian shrine, usually built in a cavern-like structure.
A local organization of cavers that typically organizes trips to caves and provides information and training for caving; a caving club.
A secretive name for a local group of underground Satanists.
A garden or roadside shrine with a small cave containing a statue of the Blessed Virgin Mary (Can we verify this sense?)
Source: wiktionary.orgSearch words containing