Etymologically, "super" means "above", and "ultra" means "beyond". So supersonic means above human hearing, ie: pitched too high, whilst ultrasonic could be either too low or too high.
John On Sun, 03 Sep 2006 05:30:28 +0100, Godfrey DiGiorgi <[EMAIL PROTECTED]> wrote: > > On Sep 2, 2006, at 1:31 PM, Adam Maas wrote: > >> You should know that Jargon definitions are often at odds with >> what's in >> the Dictonary, and for good reason (Jargon must be precise, but >> doesn't >> tend to worry about namespace collision outside the field in which its >> used). This is Jargon. > > I disagree. > > - Supersonic and ultrasonic are adjectives which mean specific > things, they're not jargon. > > - USM, pertaining to the use of ultrasonic ring motors of a specific > type used as focusing servos in 35mm cameras, is a Canon trademark/ > branding jargon. > > The use of the adjective "ultrasonic" in the above sentence means > "frequencies above the pitch of human hearing". "Ultrasonic ring > motor" is a descriptive term indicating a ring-shaped motor whose > motive force is supplied by vibrating elements, those elements > vibrating at frequencies above the pitch of human hearing. > > G > > -- Using Opera's revolutionary e-mail client: http://www.opera.com/m2/ -- PDML Pentax-Discuss Mail List [email protected] http://pdml.net/mailman/listinfo/pdml_pdml.net
