A mass tag of all images that are tagged Balloon but not tagged Inflatable, Balloonie Pony, or Hot Air Balloon as “Party Balloon” would cover the broader case that Balloon had been used for prior.
And then “Balloon” itself as a tag could be used as an implied tag for Balloonie Ponies, Hot Air Balloons, Party Balloons, etc. leaving those all searchable with the original tag.
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