Is the profligate the same as the dissolute (fasiq) Muslim? Or is there a difference between them?

Linguistically, "fujoor" (immorality/wickedness) is absolute inclination. Thus, the "faajir" (immoral/wicked person) is one who deviates from the truth, whether through transgression and disobedience or through disbelief. The Prophet, peace and blessings be upon him, described Mukraz ibn Hafs as a "faajir" (wicked man) when he was still adhering to polytheism.