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In this paper we study the Penrose limit of $AdS_5$ orbifolds. The orbifold can be either in the pure spatial directions or space and time directions. For the $AdS_{5} \Gamma\times S^5 $spatial orbifold we observe that after the Penrose limit we obtain the same result as the Penrose limit of $AdS_5 \times S^5 \Gamma$. We identify the corresponding BMN operators in terms of operators of the gauge theory on $R\times S^3 \Gamma$. The semi-classical description of rotating strings in these backgrounds have also been studied. For the spatial AdS orbifold we show that in the quadratic order the obtained action for the fluctuations is the same as that in $S^5$ orbifold, however, the higher loop correction can distinguish between two cases.
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