probably borrowed from New Latin aërometrum,
from aëro- aero-
+ -metrum -meter
Latin aerometrum is used as the name of an instrument by Johann Christoph Sturm in Collegii experimentalis sive curiosi pars secunda (Nürnberg, 1685); whether this word was taken up by other authors or recoined is uncertain. The Oxford English Dictionary records a curious earlier usage by Henry Stubbe in The Plus Ultra reduced to a Non Plus: or, A Specimen of some Animadversions upon the Plus Ultra of Mr. Glanvill, wherein sundry Errors of some Virtuosi are discovered, the Credit of the Aristotelians in part Re-advanced… (London, 1670). As is evident from the title, this work is extremely critical of the work of Joseph Glanvill, Robert Boyle, and others associated with the Royal Society. In discussing the invention and naming of the barometer, Stubbe says "The Aerometer might have been a little more Emphatical [expressive, apt]; especially considering that ἀερομετρεῖν and ἀδολεσχεῖν are Synonimous" (p. 9). The verb aerometreîn, literally, "to measure the air," was used by Xenophon to mean "to lose oneself in vague speculation," which Stubbe thought was quite appropriate for an instrument he appears to have considered pointless (on the grounds that perturbations in a barometer were caused by "elasticity" of the air, not weight, and could not be measured). (Note that adolescheîn means "to talk idly, prate, meditate.") It is doubtful if Stubbe's jeu d'esprit had any influence on subsequent use of aerometer.