Technical misnomers, ambiguous or plain incorrect terms in general usage.

[Synthtech]

I used to think that sugar diabetes was a Greek boxer.

[Circlotron]

It’s easier to say World Wide Web than www.

[GlennSprigg]

'Digital' aerials (antennas) - There is nothing digital about them its the signal that binary that's a rx or tx via a RF waveform

Yea !!.... Reminds me of the days when 'Color' TV came in, and shops tried to sell you a 'special' Color 'Aerial'   

[GlennSprigg]

I used to think that sugar diabetes was a Greek boxer.

HA !!!......   No.... that's his brother, Con. Who likes jumping out of airplanes . . . . . .
"Condescending"......   ('Con', descending )......  ok i'll shut up 

[GreyWoolfe]

I'm surprised nobody has yet mentioned "engineer" being used in place of technician, installer or operator.

If my cable TV box isn't working, I don't want the company to send an engineer. If they sent a real engineer, they'd be sitting in front of the box with a JTAG probe attached, probably spending days or weeks identifying the true root cause of whatever memory corruption causes the picture to freeze under very specific circumstances.

What I want instead is for them to send a technician, who can follow a prescribed diagnostic procedure, and who will hopefully know from experience that adding a -6dB attenuator in the signal path has a good chance of making it work reliably. Total time taken, about 20 minutes, and my cable box becomes usable again.

Back in the R&D lab, an engineer can (and should) replicate that empirical 'fix', determine exactly how and why it makes the symptoms of some underlying problem better, then fix the code and ensure the fix is rolled into to the next firmware update.

Very different skills, very different job functions, and neither could do the job of the other - yet still the confusion over the title.

When I first started with my company, we were called Field Service Engineers and that was in our email signatures.  Then, we were told not to use engineer but technician, so we had to change our digital signature to reflect this.  Now, we are back to being called engineers depending on which part of the company is sending the emails.  My official job title, however, has always been Field Service Technician, starting with Technician I, then II and now III.  It doesn't matter what anyone calls me as long as my paycheck is direct deposited every 2 weeks.

[vk6zgo]

'Digital' aerials (antennas) - There is nothing digital about them its the signal that binary that's a rx or tx via a RF waveform

Yea !!.... Reminds me of the days when 'Color' TV came in, and shops tried to sell you a 'special' Color 'Aerial'   

Not only were they "Color aerials", some of them were actually "coloured", with gold metalwork & red insulation!
Another was the " Color Compatible" BW TV sets---they had a 4.433MHz notch filter in the video amp!

[sibeen]

Grinds my gears when people use the word “shall”.
As in “you shall not do this”.
Sounds like they are looking down their nose at you.

You should probably avoid reading many of the Australian/New Zealand Standards then. In those "shall' has a defined term basically equivalent to mandatory.

[David Hess]

The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in this document are to be interpreted as described in RFC 2119.

https://www.ietf.org/rfc/rfc2119.txt

[Canis Dirus Leidy]

I hate hearing the phrases......   "AC Current", or "DC Current"..... 
'AC' means 'Alternating Current', so 'AC Current' means "Alternating Current Current"  Aarrgh....

(smiling with all 42 teeth) Want some CD and DVD disks?

P.S. Nobody mention kWt/hr (kilowatt divided by hour)? It's even mentioned in classic film have own video on Youtube:


P.P.S. And this lovely gem (google translated) from Russian sci-fi book: "The rapidity of the teenager could not fool a complex device, whose processor operates at a clock frequency of milliseconds"

[GeorgeOfTheJungle]

kW/h, yes, that's a popular one. Looks very much like km/h, that's perhaps why.

[Tepe]

calling kcal calories

[Circlotron]

Calling a spade a shovel.

[JohnnyMalaria]

atomic weight and molecular weight

Should be: relative atomic mass and relative molecular (or molar) mass

The weight of a water molecule on Earth is about 5x10^-21N whereas the relative molecular mass of water is 18.02g anywhere.

[GeorgeOfTheJungle]

Wow, you're right, it never occurred to me. But why relative?

[JohnnyMalaria]

The same number of atoms (for elements) or molecules (for compounds) as in 12g of carbon-12. This number is Avogadro's constant (6.022x10²³) and termed the mole.

Sadly, this is so rampant that even the International Union of Pure and Applied Chemistry do it.

[Nominal Animal]

Should be: relative atomic mass and relative molecular (or molar) mass

Not unless you also say "relative mass" when talking about kilograms.

The reason is that 1 u = 1 g/mol = 931.4940954 = MeV/c² = 1.660539040×10^-27 kg.

The mass itself measured or described (in atomic mass units) is absolute, not relative to anything else. Only the units are -- but so is the kilogram, too: mass in kilograms is (as of this writing) still measured relative to the SI kilogram standard.

Also, the name of the units are "unified atomic mass unit" and "molar mass". No "relative" there.

[JohnnyMalaria]

IUPAC definitions:

unified atomic mass unit
Non-SI unit of mass (equal to the atomic mass constant), defined as one twelfth of the mass of a carbon-12 atom in its ground state and used to express masses of atomic particles.

relative molecular mass
Ratio of the mass of a molecule to the unified atomic mass unit. Sometimes called the molecular weight or relative molar mass.

relative molar mass
Molar mass divided by 1g.mol^-1 (the latter is sometimes called the standard molar mass) (which in all my years of being a chemist I have never seen or heard)

My original annoyance is that nowhere does weight come into it.

I pride myself in trying to adhere to everything IUPAC but changing sulphur to sulfur - ouch, that hurt.

[JohnnyMalaria]

I'm guilty of this one informally but in scientific publications I am a stickler...

Do not use plural forms of units

e.g., 10 kilogram, not 10 kilograms

Why?

Because different languages use different ways of indicating plurals.

[Nominal Animal]

IUPAC definitions:

Bah, chemists and their weird ways. 

relative molecular mass, relative molar mass

But that's different to non-relative molecular or molar mass.

The units for (absolute) molar mass is kg/mol, usually denoted by variable M. Relative molar masses are unitless, and are usually denoted by variable M_r.  I don't understand how one can confuse the two; but then, I do physics, not chemistry, and do not recall ever seeing the relative quantities being used.

My original annoyance is that nowhere does weight come into it.

Yeah; I'm just  you with the "relative" detail.

Back to topic.  A lot of physical phenomena are named after some physicist or other scientist, but I have always had difficulty associating the two.  I much prefer descriptive names like "thermoelectric effect" over "Seebeck effect" or "Peltier effect". While the latter are not misnomers per se, I find them hard to remember and associate correctly.

[JohnnyMalaria]

Which reminds me...

Abbreviations for units. Uppercase initial letter if named after someone others lower case but lower case for the full name of the unit. Funny how ohm isn't O. It's the life sciences world that irks me with its insistence of using L for liter/litre. Yes, it may avoid confusion if you can't write for shit but it is lower case. As my physics (!) teacher used to remind us, "There was no Monsieur Litre"

[Bassman59]

'Digital' aerials (antennas) - There is nothing digital about them its the signal that binary that's a rx or tx via a RF waveform

For awhile after portable digital music players were gaining market traction, you would see "digital" headphones offered for sale. Never mind that they had the same ⅛" or ¼" TRS jack that plugged into an amplifier that was analog.

The latest thing is the idiots talking about "digital music" and "digital delivery," as opposed to the compact disc. I have to remind these idiots that "hey, the compact disc is a digital format."

[NiHaoMike]

For awhile after portable digital music players were gaining market traction, you would see "digital" headphones offered for sale. Never mind that they had the same ⅛" or ¼" TRS jack that plugged into an amplifier that was analog.

There are truly digital headphones that use USB or Bluetooth. As well as analog headphones that have buttons to control a digital device it's plugged into.

[David Hess]

Abbreviations for units. Uppercase initial letter if named after someone others lower case but lower case for the full name of the unit. Funny how ohm isn't O.

Ohms is spelled out because of the obvious homographs 0, O, and o.

I usually try to use the full name for units just to avoid confusion.

[GeorgeOfTheJungle]

Nobody uses Ω anymore?

[David Hess]

Nobody uses Ω anymore?

When I am writing or producing documentation, sure.  But computer systems and unicode are now so screwed up that the Ω symbol is increasingly unreliable.  It used to work great back when code page 437 was ubiquitous.

Firefox does not even allow me to enter it directly without issuing a page back command.