Linked from
The 13 pages that link to Thymus, each with the reason it gives.
T cellRelated: T cells acquire functional receptors and pass selection in this organ.
Immune systemRelated: It selects developing T cells before they join immune responses.
Immune toleranceRelated: Its selection process establishes a major part of central T-cell tolerance.
Parathyroid glandRelated: The inferior parathyroids descend alongside it during development.
SweetbreadRelated: The thymus is one of the two organs sold as sweetbread.