1. (

• fathom ,
• fthm ,

) a linear unit of measurement (equal to 6 feet) for water depth ;

2. (

• fathom ,
• fthm ,

) (mining) a unit of volume (equal to 6 cubic feet) used in measuring bodies of ore ;

1. (

• penetrate ,
• fathom ,
• bottom

) come to understand ;

2. (

• fathom ,
• sound

) measure the depth of (a body of water) with a sounding line ;