Complex Variations Of The Double-Mode Cepheid Variable V2853 Ori

V2853 Ori is already known as a double-mode first/second-overtone pulsator with an additional combination frequency, f(1) + f(2). Two new combination frequencies have been discovered, f(2) - f(1) and 2f(1) + f(2). The primary period has also changed at least once in the past 20 years with Delta P/P = +1 center dot 2x10(-5), equivalent to a continuous change, (P) over dot = +0 center dot 029 +/- 0 center dot 005 s/yr, which is probably consistent with a first crossing of the instability strip. The secondary period has shown discrete changes of Delta P/P = +/- 7x10(-5) on a time-scale of 2000 days. A comparison of the periods and Fourier decomposition components of V2853 Ori with other Galactic first/second-overtone Cepheids confirms it as a member of that class.