Definition of white mangrove
1
: a small shrub to moderately large tree (Laguncularia racemosa) of the family Combretaceae that grows in brackish waters along the seacoasts of western Africa and tropical America, has flowers with fine small petals and a persistent top-shaped calyx, and is locally important as a source of tannins
2
: a small or medium-sized tree (Avicennia officinalis) growing in brackish water especially along the shores of the southwestern Pacific, having leaves white beneath, and yielding hard pale lumber and usable quantities of tannin;
broadly
: any of several mangroves of the genus Avicennia
