precipitate

Concise Oxford English Dictionary © 2008 Oxford University Press:
precipitate

▶verb /prɪˈsɪpɪteɪt/ 

• 1 cause (an undesirable event) to happen unexpectedly or prematurely.

• 2 cause to move suddenly and with force.

  ■ (precipitate someone/thing into) send someone or something without warning into a particular state or condition.

• 3 Chemistry cause (a substance) to be deposited in solid form from a solution.

  ■ cause (drops of moisture or particles of dust) to be deposited from the atmosphere or from a vapour or suspension.

▶adjective /prɪˈsɪpɪtət/ done, acting, or occurring suddenly or without careful consideration. ▶noun /prɪˈsɪpɪtət, -teɪt/ Chemistry a substance precipitated from a solution.

– derivatives
precipitable adjective,
precipitately adverb,
precipitateness noun,
precipitator noun.

– origin C16 (orig. ‘hurl down, send violently’, later ‘cause to move rapidly’): from L. praecipitat-, praecipitare ‘throw headlong’, from praeceps, praecip(it)- ‘headlong’, from prae ‘before’ + caput ‘head’.