An "a" with a line over it is the phonetic symbol for the sound of a long "a", as in play.
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In a prescription it means "before". Your Doctor might write a Rx like.....ibuprofen 100mg PO QD BID a.c. This means to take ibuprofen 100mg by mouth everyday twice daily before meals, and this is just a silly example, so don't take it seriously.
The prescription could have the "a.c." or just the "a" with a line over it, but that's pretty much what it stands for.
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Certain languages may put accent marks over an "a", as part of how they spell their words.
S with a line over it means without, and a with a line over it means before.
A lower case a with a line over it means before in medical terminology. For instance, ac means before mealsLower case a with a line over it stands for "ante," and means "before" in medical terms.
With, without, before, and after are each symbolized with a single letter with a horizontal line written over it:With: cwithout: sbefore: aafter: p
A line over a whole number means that number repeats for an infinite number of times.
It could represent a vector.
in order for it to be a goal the ball is to completely pass the goal line
Tesco
The marks you're describing represent the number 1 in a prescription. The horizontal line and dot are to help prevent reading errors.
If you mean what does an o with a line over it means, it means that there is emphasis on the o. Such as, Rōb would be pronounced like Robe, not Rob. If you mean how to type it, I just searched what is an o with a line over it? in google, then copy and pasted it onto my document. Hope this helped.
if used in a decimal it means that the number it is over is repeating ex) 27.33333333333333 instead you could write 27.3 with a line over the 3
It can mean that it is a vector.
it means zero or close-ist to zero