Sweetbread \Sweet"bread`\, n.

1. Either the thymus gland or the pancreas, the former being called neck, or throat, sweetbread, the latter belly sweetbread. The sweetbreads of ruminants, esp. of the calf, are highly esteemed as food. See Pancreas, and Thymus.

2. (Anat.) The pancreas.

Source: Webster's Revised Unabridged Dictionary (1913)