What does a circle with a slash through it mean?

[Wisco52]

I am reading European engineering publications, and the circle with a slash shows up about half of the time in front of length measurements. For example, Ø15 x 1.12 mm. What does this mean?

 

[russ_watters]

Diameter.

 

[Wisco52]

Makes sense, thanks.

 

[symbolipoint]

Could be a representation of digit ZERO.

 

[Gary Feierbach]

Diameter is probably correct in your case but Ø is often used to distinguish zero form O. I have also seen it used for the greek letter phi on occasion.

 

[Baluncore]

For example, Ø15 x 1.12 mm.

The format would make sense if it described a 15mm diameter bolt, threaded with a 1.12mm pitch thread.
But 1.12mm is not a standard metric pitch.

 

[Robert Gross]

It is a left-over from ancient computer programming practice. Back when data was entered by writing on paper than having it keypunched (are you old enough to know what a keypunch was?) and all alphabetic data was upper case, you needed some convention to distinguish O (letter) from 0 (zero) They look the same on paper, on the punch card, and on many printers. That goes back 50 years - I still do it out of habit.

 

[Svein]

... and to add to the confusion: Ø is a Norwegian/Danish character, (Oe ligature) equivalent to the Ö in German and Swedish.

 

[lychette]

I am reading European engineering publications, and the circle with a slash shows up about half of the time in front of length measurements. For example, Ø15 x 1.12 mm. What does this mean?

this means a disc of diameter 15mm and thickness 1.12mm