fugacity

UK: /fjuːˈɡæsɪtɪ/

Collins Concise English Dictionary © HarperCollins Publishers::

fugacity / fjuːˈɡæsɪtɪ/ noun

1. Also called: escaping tendency a property of a gas, related to its partial pressure, that expresses its tendency to escape or expand, given by d(log_ef) = dμ/RT, where μ is the chemical potential, R the gas constant, and T the thermodynamic temperature

WordReference Random House Unabridged Dictionary of American English © 2026

fu•ga•cious  (fyo̅o̅ gā′shəs), adj. 

1. fleeting; transitory:
   a sensational story with but a fugacious claim on the public's attention.
2. Botany falling or fading early.

• Latin fugāci- (stem of fugāx apt to flee, fleet, derivative of fugere to flee + -ous
• 1625–35

fu•ga′cious•ly, adv. 
fu•ga′cious•ness, fu•gac•i•ty  (fyo̅o̅ gas′i tē), n.