Are tittles ("i" and "j") ascenders?

Question

All typography sites seem to be in agreement about most typefaces:

• The lower-case letters b, d, f, h, k, l, and t usually have ascenders.
• The lower-case letters i and j usually have a dot on top, called tittle if one really needs a name for them.

But are tittles ascenders? A few sites boldly assert this. For example, search on Google for what letters have ascenders and you will get this page, which proudly proclaims that i and j are (sic) ascenders. But that page is pretty dubious since it also claims that all capital letters have ascenders and it's not very precise about a letter having an ascender vs. a letter being and ascender.

More reputable-looking (IMHO) sites seem to just skirt the question. They’ll proudly declare that b and h are two letters that have ascenders and stay quiet about the other letters.

Is this a thing where there is general agreement among professionals and a lot of us amateur typographers are wrong? Or is this a cultural thing where there are competing schools of thought that have had schisms about this issue but typographers are so polite everyone has just agreed to not mention it? Am I about to restart a culture war by asking this question?

And how about diacritics?

Answer 1

Typographic terminology needs not be as rigorously defined as say mathematical terminology. Nobody is going to make statements like: “If and only if a glyph has ascenders, its left kerning must be doubled.” Rather, it is usually clear from context whether an ascender refers to everything extending above the median or excludes tittles and diacritical marks.

The same goes for whether tittles are diacritical marks or not. In some respects they behave like them, in others they don’t. Moreover, this can depend on the language, e.g., i tittles behave more like diacritical marks in Turkish and Azeri.

For example:

• The most common ligatures feature f and a following letter with an ascender avoiding a collision of ascenders.

  Here, it is clear from context that ascender includes tittles, since the collision problem applies to both.

• The style set ss01 extends most ascenders and descenders with elegant swashes.

  Here, ascenders does not include tittles, since extending those with swashes does not make sense.

Thus, there is little incentive to establish a unified definition of ascender, let alone start a schism or culture war on this.

Answer 2

There are two entries for the word "ascender" in this context in the OED.

b. spec. in Typography (see quot. 1867).

1867 T. MacKellar Amer. Printer (ed. 3) 48 Ascenders, all the capital letters, and the b, d, f, h, i, j, k, l, t, so called because they ascend to the top of the body of the types. A colloquial phrase for Ascending Letters.

c. In Printing and Palæography, an ascending stroke; a stroke which extends above the body of a letter.

1934 in Webster's New Internat. Dict. Eng. Lang.

1938 A. H. Smith in London Mediæval Stud. I. 204 After neah there is a long ascender which may be part of h or l or b.

1955 C. E. Wright Bald's Leechbook 24 The hook at the top of the ascender of b.

Source: The Oxford English Dictionary Online

This would seem to suggest that both definitions b and c are usable, however I will draw your attention to the date of the sole attestation, 1867, for entry b, and the fact that this is described as a "colloquial phrase", which would seem to suggest that the actual full term is "Ascending Letter".

Note that definition c would exclude capital letters, and also i and j.

In my opinion therefore, a tittle is not an upward extending stroke. It's simply a dot (a square/circle/ellipse). And the letters "i" and "j" are ascending letters, not "ascenders", except perhaps when using colloquial language, or depending ultimately on how formal you want to be, or how technical you want to get. Also tittles aren't used as diacritics in English, but they may be viewed that way in other languages — something to ask a linguist about perhaps.