Warner
Usually from an old personal name, though in some cases it may have been influenced by the word warrener, a keeper of game.
The #375 most common surname in the United States (2010 Census) — about 1 in every 3,685 Americans shares it.
Etymology
The surname Warner is best explained as coming from an old Germanic given name, recorded in medieval Latin forms such as Warnerus and Waruerius. That name belongs to the widespread Germanic war-name family built on elements meaning “army” and “protector” or “warrior.” Some later writers also noted that in a few cases Warner may have been confused with, or reshaped from, warrener, the occupational word for a keeper of rabbits or game.
History
Medieval records in England already show Warner as an established surname, including Domesday and 12th-century forms. Because it was also used as a baptismal name, the surname could arise independently in more than one family line. The spelling has remained relatively stable, which helped it survive as a common English surname into modern times.
Origin
Regions
Variant spellings
Fun fact
Lower noted that Warner was already written in Domesday forms, showing how early this surname entered the English record.
From the historical record
“we also find 'atte Werne'. WARNER (A.-Fr.-Teut.) i the French War- mer, Guamier, Guamer,' Giimier, O. Teut. Warinherii, Warinhar(i, Werinherii, Wemhere, &c. [v. under Warin, and + O.Sax. O.H.Ger. heri, hart = O.E, here = O.N. her-r '= Goth, harji-s, army] ' Warner-US is the form in Domesday- Bk. and the i2th-cent.…”
— Surnames of the United Kingdom: a concise etymological dictionary (2 vols in 1)