moot
MOOTadjMeaning open to debate; also, no longer worth arguing about
Memory hook MOOT = MUTE: nothing left to argue. Pip and Zoe argue over who gets the last cookie, until they see the dog already ate it. The argument goes mute: the question is moot.
Whether to hold the picnic indoors became moot when the rain stopped.
In context The class argued for an hour about which bus to take on the field trip, but the question was moot: the trip had already been canceled because of the storm.
Similar debatable, arguable, academic, irrelevant
Opposite settled, relevant
From Old English mot, a meeting where people gathered to debate questions.