noun
also adenosinetriphosphoric acid
: an amorphous ester C 10 H 12 N 5 O 3 H 4 P 3 O 10 of adenosine and triphosphoric acid that occurs in living cells, especially in muscle tissue, where its enzymatic hydrolysis to adenosine diphosphate and adenylic acid releases phosphate and available energy for the work of muscular contraction, and that plays a fundamental role in most other biochemical processes that either produce or require energy (as biological oxidations) — called also adenylpyrophosphate, ATP