metastable

• They are metastable, and will eventually convert to graphite -- but this takes hundreds of millions of years, so on human time scales diamond behaves like an ordinary stable solid. —  F ;SF; - vol 091 issue 02 - August 1996
• They manipulate the water in the xylem under negative pressure - what's called a metastable liquid state - right on the verge of becoming a vapor. —  The Open Piehole
• Setup or hold violations cause the output of the flip-flop to enter a symmetrically balanced transient state, called a metastable state. —  EE Times-Asia
• However, its persistence to the end of the runs was apparently metastable, as it should have reacted with the final solutions to produce pyrite or pyrrhotite. —  CiteULike: Everyone's library
• Technetium-99m, where "m" stands for "metastable" -, one resorts to another isotope, Molybdenum-99. —  Backreaction

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