Aliasing is a common problem in signal processing that is caused by undersampling or oversampling, leading to errors and distortion in the output. Synonyms for aliasing include foldover, frequency modulation, image frequency, and spectral leakage. Foldover is an aliasing effect that occurs in undersampling, where high-frequency signals are misrepresented as lower frequencies. Frequency modulation aliasing is caused by the interference between signals with different frequencies. Image frequency aliasing occurs in radio transmission when the local oscillator signal leaks into the receiver's output. Spectral leakage aliasing occurs when a spectral component in a signal contributes to adjacent frequency bins. Understanding these synonyms is important for identifying and mitigating aliasing effects in signal processing applications.