Probably stem...
Celery is a special part of leaf structure called petiole
Stem
stems
stems
stems
No celery is a plant with many edible stalks. However Celeriac (also know as celery root) a relative of celery but is not part of the same plant.
the celery "stick" is the stem and the leaves at the top the leaves of the plant; both the leaves and stems are edible
Celery is a vegetable. It is just the swollen petiole (part of the leaf) of the plant.
stem (and leaves) but the part we eat are stems
When you eat celery, you are consuming the stalks of the plant. The stalks are the long, fibrous structures that grow upward from the base and support the leaves. Celery is a type of marshland plant in the Apiaceae family, and both the stalks and leaves are edible, but the stalks are the most commonly eaten part.
The bottom of a celery plant is called the "base" or "crown." It is the part from which the stalks grow and is often where the roots emerge. In culinary terms, this section is sometimes referred to as the "root end" when preparing celery for cooking or eating.
Celery is the stem of a plant.