Definition of white alder
1 a
: any of several native alders (as Alnus rhombifolia) of western North America
b
: gray alder
2
: any shrub or tree of the genus Clethra
3
: a southern African tree (Platylophus trifoliatus) of the family Cunoniaceae
4
: privet andromeda
5
: a winterberry (Ilex verticillata)
