packing fraction

American  

noun

1. Physics. a measure of the stability of an atomic nucleus, equal to 10 4 multiplied by the mass defect and divided by the mass number.

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packing fraction British  

noun

1. a measure of the stability of a nucleus, equal to the difference between its mass in amu and its mass number, divided by the mass number

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packing fraction Scientific  

/ păk′ĭng /

1. The ratio of the total volume of a set of objects packed into a space to the volume of that space.

2. The difference between the isotopic mass of a nuclide and its mass number, divided by its mass number. The packing fraction is often interpreted as a measure of the stability of the nucleus.

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Etymology

Origin of packing fraction

First recorded in 1925–30

Example Sentences

Chip titan Nvidia has launched Nemotron, a family of cheaper models that is gaining traction, and also has backed Reflection, a startup building open-source AI.

From The Wall Street Journal • Jun. 12, 2026

Analysts project Intel’s server CPU sales to exceed $40 billion by 2030, and its foundry business is gaining traction.

From Barron's • Jun. 11, 2026

Although it is still unprofitable, the business is steadily gaining traction with customers.

From Barron's • Jun. 11, 2026

He pointed to the company’s 800G and 1.6T optical interconnects, which are gaining traction as traditional copper-based wiring faces limitations in artificial-intelligence data centers.

From MarketWatch • May 27, 2026

Smart glasses are gaining traction as "that next modality" to follow the success of the smartphone, she added.

From BBC • May 19, 2026