As nouns the difference between undecane and undecyl
is that undecane is undecane while undecyl is (organic chemistry|especially in combination) any univalent radical derived from an undecane.
undecane
English
Noun
(
en noun)
(organic compound) Any of many isomers of the aliphatic hydrocarbon having 11 carbon atoms, but especially n-undecane CH3(CH2)9CH3
undecyl
English
Noun
(
en noun)
(organic chemistry, especially in combination) Any univalent radical derived from an undecane