Why does ボウル use a vowel kana rather than a long vowel mark?


It seems like both ボウル and ボール are valid Japanese words. The general
impression I get is that using long vowel marks ("ー") are the norm for words
written in katakana.

In [Why are long vowels represented differently in hiragana and
katakana?](https://japanese.stackexchange.com/questions/21272/why-are-long-
vowels-represented-differently-in-hiragana-and-katakana) , explanations of
vowel kanas being used instead include words that have kanji, or breaking up
the sound. Maybe I'm just ignorant of how "bowl" is pronounced in either
British English or American English, but neither explanation seems plausible.
Why is ボウル spelt using a vowel kana?

Neither the [Japanese Wikipedia article on
ボウル](https://ja.wikipedia.org/wiki/%E3%83%9C%E3%82%A6%E3%83%AB), the [Japanese
edition of
Wiktionary](https://ja.wiktionary.org/wiki/%E3%83%9C%E3%82%A6%E3%83%AB), or
the [English
edition](https://en.wiktionary.org/wiki/%E3%83%9C%E3%82%A6%E3%83%AB) have an
explanation for this particular word.




「ボウル」("bowl") is still often written 「ボール」 as very few people (loanword
pronunciation nazi types), actually pronounce the two differently. 「ボウル」 is
pronounced 「ボール」 by the rest of the nation.

(I never even knew that a sound like 「オウ」 existed in this world until I
started learning English in junior high school. I am sure you have heard
Japanese-speakers pronounce "Oh, no!" as 「オーノー」.)

One major reason that some prefer the spelling 「ボウル」 would be that 「ボール」 is
already reserved for "ball". The former would just look a bit cooler to
certain people, but as native Japanese-speakers, we all know that to pronounce
「ボウル」 in 3 syllables is highly counterintuitive. It will simply make you stick
out in the Japanese-speaking world.




「ボウル」("bowl") is still often written 「ボール」 as very few people (loanword
pronunciation nazi types), actually pronounce the two differently. 「ボウル」 is
pronounced 「ボール」 by the rest of the nation.

(I never even knew that a sound like 「オウ」 existed in this world until I
started learning English in junior high school. I am sure you have heard
Japanese-speakers pronounce "Oh, no!" as 「オーノー」.)

One major reason that some prefer the spelling 「ボウル」 would be that 「ボール」 is
already reserved for "ball". The former would just look a bit cooler to
certain people, but as native Japanese-speakers, we all know that to pronounce
「ボウル」 in 3 syllables is highly counterintuitive. It will simply make you stick
out in the Japanese-speaking world.

