Obturate \Ob"tu*rate\, v. t. [imp. & p. p. {Obturated}; p. pr. & vb. n. {Obturating}.] [L. obturatus; p.p. of obturare.] To stop or close, as an opening; specif., (Ordnance), to stop (a gun breech) so as to prevent the escape of gas in firing. [Webster 1913 Suppl.]