creatine

 
Pronunciation: /ˈkriːətiːn/

noun

[mass noun] Biochemistry
  • a compound formed in protein metabolism and present in much living tissue. It is involved in the supply of energy for muscular contraction.
    • A guanidine derivative, usually present as a phosphate; chemical formula: C4H9N3O2

Origin:

mid 19th century: formed irregularly from Greek kreas 'meat' + -ine4