The term "cropped up again" refers to the appearance of something that has already occurred, resurfaced or re-emerged after a period of absence. Its antonyms include terms such as disappeared, vanished or dissolved, which indicate that something has ceased to exist, vanished from sight or been completely eradicated. Other antonyms that imply the opposite of "cropped up again" include terms such as subsided, abated, diminished or waned, which indicate a reduction or decline in intensity over time. These terms provide alternative ways of describing the absence of something that has previously been present or active, and can be useful in providing a more nuanced description of a particular situation.