- an Old English word,
 - a Cornish word originating in Devonshire,
 - a Caithness surname of local origin in Scotland from the small place of the name near Dunnet,
 - the surname HAM of French origin does not have to be translated into English, it means the same and is spelled the same.
 - 'Ham' has been referred to as an Anglo-Saxon word meaning home, and in Somerset, England more closely resembling the Low German 'hamm' low-lying pasture land, or a meadow near a river (pratum sepe circumdatum) and not to be confounded with the 'Anglo-Saxon' word for home.¹
 - and it is also referred to as a Celtic word.

  The Celtic word "ham" means a place name, such as a home or farm. The Old English word "hamm" meant an enclosed piece of land, or a low lying land by a stream. The most common Old English terms denoting habitiation are "ham" and "tun." "ham" is the more ancient, and more frequently compounded with folk names. The term "tun" originally meant fence or hedge, then eventually came to mean an estate or manor, then gradually came to mean a "hamlet" or "Village." Today, the version of "tun" that we are familiar with is now called a "town."  Examples of combinations of the word would be Hampton, Higham, and Asheldham.

¹ According to Frederic Thomas Elworthy, "The West Somerset Word-Book," English Dialect Society, 1888.
    (Courtesy of correspondence in April, 2015 with Jon Hamm of East Brent, Somerset.)

timeline:

  378 AD -  A fire destroys the city of Ham in the Department of the Somme, France
  500 AD -  The Caithness word would date from this time frame, referring to the location in Scotland near Dunnet.
  765 AD -  Higham Upshire dates from this period.
  876 AD  - The City of Ham in France becomes the capital of a small country called "Hamois," which by 888 becomes attached to Vermandois.
  900 AD  -  The City of Ham in France is used to describe the location of the Lords of that region.
  1200 AD - The HAM place name begins to be used more widely to describe the location of local inhabitants in England.
  1226 AD - The city of Hamm is founded in west central Germany in the Ruhr district, southeast of Munster.

videos:

    HAM Surname Counties of Origin in England   (3 minutes, 4 MB)

   HAM Surname Counties of Origin in Virginia   (3.5 minutes, 5 MB)

   HAM Surname Counties of Origin in North Carolina   (3.5 minutes, 5 MB)

further reading:

Place Names of Sussex  - you'll need to search for "Ham."

Regia Anglorum - The Language of the Anglo-Saxons and Vikings:

http://www.regia.org/languag.htm

To view the distribution of the Danes' influence on names in England:

http://www.viking.no/e/england/danelaw/ekart-danelaw.htm

references:

     A Short History of the HAM Surname in Virginia & NC

"The Origin of English Place Names," by P. H. Reaney, Publ. Routledge and Kegan Paul. London, Boston, Melbourne, and Henley. 1994

Some 14th century names can be found in:

"A History of Surnames of the British Isles," by C. L. L'Estrange Ewen MacMillan Company, NY 1931.

"The Surnames of Scotland, Their Origin, Meaning, and History" by George F. Block, PHD, NY Public Library, NY 1946.

"Epytomological Dictionary of Family and Surnames of France," by Albert Dauzat, professor, 3rd edition. Larousse Bookstore, 17, street of Montpamasse and 114, Raspail Boulevard, Paris. 1951

"A Dictionary of Surnames," by Hanks and Hodges, 1988.