catalysis
n. (வேதி.) இயைபியக்கத்தை ஊக்கும் ஆற்றல், தான் மாறாமலேயே மற்றப்பொருள்களில் வேதியல் மாற்றமுண்டாக்கத் துணைசெய்தல்.
Ca*tal"y*sis, n.; pl. Catalyse. Etym: [ML., fr. Gr. 1. Dissolution; degeneration; decay. [R.] Sad catalysis and declension of piety. Evelyn. 2. (Chem.) (a) A process by which reaction occurs in the presence of certain agents which were formerly believed to exert an influence by mere contact. It is now believed that such reactions are attended with the formation of an intermediate compound or compounds, so that by alternate composition and decomposition the agent is apparenty left unchanged; as, the catalysis of making ether from alcohol by means of sulphuric acid; or catalysis in the action of soluble ferments (as diastase, or ptyalin) on starch. (b) The catalytic force.