There are 13 words that start with 'bathy'.
| bathyal | bathymetry | 
| bathyscaph | bathymetric | 
| bathyscaphe | bathyscaphs | 
| bathysphere | bathymetries | 
| bathypelagic | bathyscaphes | 
| bathyspheres | bathymetrical | 
| bathymetrically | |
Note: These 13 words that start with 'bathy' are found from the USA & Canada version of the tournament Scrabble word list.