Definition - What does Lignified mean?
Lignified means that green parts of a plant, such as those of a grapevine, have turned to wood.
As grapevines grow and age, their trunks and some branches will turn woody and resemble the trunk of an old, fibrous tree. This maturation is necessary so that the vine can more efficiently transport necessary water, nutrients and minerals throughout the rest of the plant.
WineFrog explains Lignified
Lignified vines are those which have matured and grown to have a main trunk, cordons and spurs.
The lignified anatomy has an outer covering called xylem. This tissue is involved in conducting certain processes within the vine. Water and nutrients are transported here and keep the rest of the vine functioning via photosynthesis, cellular respiration and thus the division of cells to create the seasonal anatomy of the grapevine; shoots/canes, buds, leaves and grapes.