Other forms: bubbles
A bubble is a ball of air trapped in a liquid or in glass. Round, because that is the shape with the least surface for the volume.
Soap bubbles hold together by surface tension and burst when the water evaporates from the film. Economics borrowed the word for a market where prices rise on nothing and then pop, and the housing bubble and the dot-com bubble are the standard examples. Living in a bubble means being cut off from other views, and the pandemic gave the word yet another sense.
1nounbubbleA thin sphere of liquid enclosing air.
“A bubble of air came up through the mud.”
2noununsustainableAn unsustainable rise in prices or a sealed-off social group.
“Everybody knew the bubble would burst eventually.”
Partly imitative of the sound, also influenced by burble. Compare Middle Dutch bobbe (“bubble”) > Dutch bubbel (“bubble”), Low German bubbel (“bubble”), Danish boble (“bubble”), Swedish bubbla (“bubble”). The word was first used in its economic sense in association with the collapse of the South Sea Company in 1720, based on the metaphor of an inflated soap bubble bursting.
Etymology from Wiktionary, CC BY-SA