Antidiuretic hormone, thyroid, water, dehydration pick the odd one out and mention the category

Thyroid is the odd one out , since it is an endocrine gland.
​​​​​​Antidiuretic hormone (ADH) is a hormone that causes the kidneys to release less water, decreasing the amount of urine produced.  Thus ADH , water and dehydration is related.

Regards