The best way to identify the difference between a nectarine and peach is by the lack of fuzz on the nectarine.
The nectarine tree is almost identical to the peach in appearance, culture and care.
Genetically, the only difference between peaches and nectarines is the lack of fuzz on the nectarine skin.
Together with a colleague was the first to recognize and characterize a novel disorder in nectarine named nectarine pox.
British Dictionary definitions for nectarine
nectarine
/ˈnɛktərɪn/
noun
1.
a variety of peach tree, Prunus persica nectarina
2.
the fruit of this tree, which has a smooth skin
Word Origin
C17: apparently from nectar
Word Origin and History for nectarine
n.
type of peach with smooth skin, 1660s, noun use of adjective meaning "of or like nectar" (1610s; see nectar + -ine (1)). Probably inspired by German nektarpfirsich "nectar-peach." Earlier in English as nectrine.