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Fathom

2 stages from Old English to English.

Today it means a unit of depth of six feet; to understand after much thought

Where does the word "fathom" come from? It comes from Old English fæþm, adopted directly into English (1600s).

1
Stage 1 of 2
fæþm
Old English · medieval
"embrace; arm-span"
'outstretched arms, embrace', and the length of the arms spread out
2
Stage 2 of 2
fathom
English · 1600s
"six feet; to understand"
fixed as six feet for measuring water depth, and so 'to get to the bottom of' something; Mark Twain's pen name comes from the Mississippi call 'mark twain', two fathoms
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Read the full story

Fathom’s story begins in Old English: fæþm meant “embrace; arm-span.” 'outstretched arms, embrace', and the length of the arms spread out. It reached English by 1600s as fathom. Fixed as six feet for measuring water depth, and so 'to get to the bottom of' something; Mark Twain's pen name comes from the Mississippi call 'mark twain', two fathoms. Today, fathom means a unit of depth of six feet; to understand after much thought.