lig·ni·fy (lĭg'nə-fī') v.
lig·ni·fied, lig·ni·fy·ing, lig·ni·fies
v.
intr. To turn into wood or become woody through the formation and deposit of lignin in cell walls. v.
tr. To make woody or woodlike by the deposit of lignin. lig'ni·fi·ca'tion (-fĭ-kā'shən) n.