Neologism include "laser" (1960) from Light Amplification by Stimulated Emission of Radiation, "robotics" (1941), "agitprop" (1930). The term "neologism" is first attested in English in 1772, borrowed from French "néologisme" (1734). A proponent of a new word or doctrine may be called a neologist. Neologists might study cultural and ethnic vernacular. The term "neologism" has a broader meaning that includes not only "an entirely new lexical item" but also an existing word whose meaning has been altered. Sometimes, the latter process is called "semantic shifting", or "semantic extension". Neologisms are distinct from a person's "idiolect", one's unique patterns of vocabulary, grammar,
Stimulated emission in such an excited state may thus result in radiation which has a narrow spectrum (centered around one wavelength of light), but the individual photons would have no common phase relationship and would also emanate in random directions. This is the mechanism of fluorescence and thermal emission. An external electromagnetic field at a frequency associated with a transition can affect the quantum mechanical state of the atom without being absorbed. As the electron in the atom makes a transition between two stationary states (neither of which shows a dipole field), it enters a transition state which does have a dipole