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In this study, we examine the effect of noise superimposed on a steady, incompressible mean flow for a circular cylinder undergoing transverse oscillations. Numerous amount of studies conducted in free vibration study of circular cylinders have been carried out in the deterministic environment. Randomness in the oncoming fluid and its effect on the overall dynamical behavior of the system is a likely scenario that has not received its due attention in the community. We use a Duffing-Van der pol combined system to make this study. The noise, which can be inherent in any flow, was modeled in our system mathematically through a uniform distribution. We observe that a multiplicative noise brings in major qualitative and quantitative changes on the structural response compared to the deterministic cases. Noise seems to have major effects on the structural amplitude, the onset and the range of lock-in. The noise, depending on its coefficient of intensity has a role in advancing the lock in regime. The qualitative changes in the response dynamics due to the addition of noise have been studied. It has been seen that the system undergoes a P (phenomenological) bifurcation in the stochastic environment. This has been characterized by observing the change in the probability density functions (pdf) of the responses with increase in mean reduced velocity (U) as shown in figure 1, showing typical pdfs for non lock-in and lock in states, for a very low intensity noise. As we increase the mean velocity, we have a unimodal pdf for the pre-lock in response (fig. 1(a)), bi modal pdf for the lock-in state (fig 1(b)). It was also seen that the stochastic environment brings noticeable differences in the structural response, mainly when the system is in the pre lock-in or post lock-in regime. These effects start to become very prominent, when the noise intensity gets higher. Upon performing a Fourier analysis of the same, it was seen that the non lock-in states exhibited multiple frequencies. Further, it is found that characterization of these states using pdfs alone is not sufficient to determine the type or evolution of these responses. In order to get a better view, we analyze the structural responses using the time series tools such as recurrence plots, Poincare maps. These analyses are helpful in determining the states through which the system passes, during the change in the bifurcation parameter. It is observed that the evolution of the system behavior occurred in an intermittent manner near the bifurcation to lock-in. Further, it is seen that the non lock-in states were characterized by quasiperiodic behavior depending on the frequencies present.