The given name Eric is derived from the Old Norse name Eiríkr (or Eríkr in Eastern Scandinavia due to monophthongization). The first element, ei- is derived either from the older Proto-Norse *aina(z) meaning "one" or "alone" or from Proto-Norse *aiwa(z) meaning "ever" or "eternal". The second element -ríkr derives either from *rík(a)z meaning "ruler" or "prince" (cf. Gothic reiks) or from an even older Proto-Germanic *ríkiaz which meant "powerful" and "rich". The name is thus usually taken to mean "one ruler" or "eternal ruler" or "ever powerful," etc.

The most common spelling in Scandinavia is Erik. In Norway, another form of the name (which has kept the Old Norse diphthong) Eirik is also commonly used. In Finland, the form Erkki is also used. The modern Icelandic version is Eiríkur, while the modern Faroese version is Eirikur. Éric is used in French, and in Germany Eric, Erik and Erich are used.

Although the name was in use in Anglo-Saxon Britain, its use was reinforced by Scandinavian settlers arriving before the Norman Invasion. It was an uncommon name in England until the Middle Ages, when it gained popularity, and finally became a common name in the 19th century. This was partly because of the publishing of the novel Eric, or, Little by Little by Frederick William Farrer in 1858.

The rowans or mountain-ashes are shrubs or small trees in genus Sorbus of family Rosaceae. They are native throughout the cool temperate regions of the Northern Hemisphere, with the highest species diversity in the mountains of western China and the Himalaya, where numerous apomictic microspecies occur. The name rowan was originally applied to the species Sorbus aucuparia, and is also used for other species in Sorbus subgenus Sorbus. Rowans are unrelated to the true ash trees which belong to the genus Fraxinus, family Oleaceae, though their leaves bear superficial similarity.

The name "rowan" is derived from the Old Norse name for the tree, raun. Linguists believe that the Norse name is ultimately derived from a proto-Germanic word *raudnian meaning "getting red" and which referred to the red foliage and red berries in the autumn. Rowan is one of the familiar wild trees in the British Isles, and has acquired numerous English folk names. The following are recorded folk names for the rowan: Delight of the eye (Luisliu), Mountain ash, Quickbane, Quickbeam, Quicken (tree), Quickenbeam, Ran tree, Roan tree, Roden-quicken, Roden-quicken-royan, Round wood, Round tree, Royne tree, Rune tree, Sorb apple, Thor's helper, Whispering tree, Whitty, Wicken-tree, Wiggin, Wiggy, Wiky, Witch wood, Witchbane, Witchen, Witchen Wittern tree. Many of these can be easily linked to the mythology and folklore surrounding the tree. In Gaelic, it is caorann, or rudha-an ("red one", pronounced similarly to English "rowan").