champon

[potetjp]

William H. Baxter's remark leads me to suggest that the case of Jap.
_champon_  might be comparable to that of Jap. _tabako_ "tobacco".
The Jap. term _tabako_ was borrowed from a Western language, probably
Portuguese. Its kanji transcription (Nelson 1969: #2784, § 9) is completely
unrelated to its kana transcription, although it is read the same way. The
kanji transcription only gives the meaning: _EN/kemu_ (Nelson 1969: # 2784)
"smoke" + _SOu/kusa_ (Nelson 1969: # 3939) "grass", but it is not read
_*ENSOu_,  and is not transcribed in kana as _*e-n-so-u_. [SOu = so:]
Similarly, the kanji transcription of _champon_ must be aimed at
representing the meaning rather than the pronunciation, with the advantage
that in this case the 1st syllable fits.
It would be interesting if a japonologist gave his opinion.
Jean-Paul G. Potet