white alder whi·teal·der uncommon noun 1. tree of western United States Synonymswhite aldermountain alderAlnus rhombifolia 2. shrub of eastern and southern coastal United States having beautiful racemes of spice-scented white flowers Synonymssweet pepperbushpepper bushsummer sweetwhite alderClethra alnifolia Related words Word family white-alder family Broader terms shrubalder Parts Alnus WordNet 2.1 (Princeton University). WordNet 2.1 Copyright Princeton University. All rights reserved.
