Dhatu

Dhātus (dhä·tōōs), n.pl. ( from Sanskrit धातु dhātu - layer, stratum, constituent part, ingredient, element, primitive matter ) in Ayurveda, the seven fundamental principles (elements) that support the basic structure (and functioning) of the body.

They consist of:

   Rasa dhatu (Lymph)
   Rakta dhatu (Blood)
   Mamsa dhatu (Muscles)
   Medha dhatu (Fat)
   Asthi dhatu (Bone)
   Majja dhatu (marrow (bone and spinal))
   Shukra dhatu (Semen)

Traditional texts often refer to the above as the Seven Dhātus (Saptadhātus). Ojas is known as the eighth Dhātu, or Mahādhātu (superior, or great dhātu).