English
pseudorapidity
From pseudo- + rapidity.
Formed from pseudo- + rapidity
Proto-Indo-European *h₁reh₁p- ‘to take away, snatch’
…
Latin rapiō ‘to snatch (oneself)’
Latin rapidus ‘rapid, swift’
Latin rapiditas ‘swiftness, velocity, rapidity’
French rapidité ‘swiftness, fastness, quickness’
English rapidity
Today it means
noun A measure of the velocity of a particle relative to that of a beam of particles, approximated by a function of its angle.
Language periods are conventional ranges, not dates for this word.
Etymograph / pseudorapidity