"comforter"

I have [k@mfI4@`].

I say it like that too. I'm from California, by the way.

I myself have [ˈkʰʌ̃mfʁ̩ɾ̥ʁ̩ː] for "comforter", which lacks such partial derhoticization.

I have partial loss of rhoticity in "particular" as well. I say /p@tIkjul@`/.

I preferve rhoticity in "particular" ([pʰʌʁˈtʰɪʔkjəːɰʁ̩ː]) but have partial loss of it in "caterpillar" ([ˈkʰɛ̯æɾ̥əˌpʰɪːɰʁ̩ː] or [ˈkʰɛ̯æːə̯ˌpʰɪːɰʁ̩ː]). Mind that "caterpillar" seems to be a matter of it being phonemically frozen, at least in my dialect, and the partial loss of rhoticity in it seems to be completely unproductive.

I have such loss of [r\] or [r\=] in the following words:

"comforter" [kVmfI4r\=]
"particular" [p@t_hIkjulr\=]
"caterpillar" [k{4@pI5r\=]
"surprise" [s@praIz]
"governer" [gVv@nr\=]
"mirror" [mI_r\]
"error" [E_r\]
"terror" [t_hE_r\]
"frustrate" [fVstr\eIt]
"infrared" [Inf@r\Ed]
"rural" [r\U5=]

<<v\>>

Are you trying to imitate Elmer Fudd?

Of all of those, the only ones that I really ever derhoticize at all are "surprise" (as [ˈsʌʔpʁaːɪ̯s]), "governor" (as [ˈgʌːvə̃ːnʁ̩ː]), and "mirror" (as [ˈmɪːʁ]). However, "infrared" is very frequently modified via metathesis at the phonemic level in my dialect as [ˈɪ̃fʁ̩ːʁɜ̩ːd̥].

(And "caterpillar", as previously mentioned, of course.)

What about "microphone", "microwave" and "intracoastal"? I have a similar thing with those, [maIkr\=f7Un], [maIkr\=weIv] and [Intr\=k7Ust5=] as "infrared" [Infr\=r\Ed].

I don't have such for those, having "microphone" [ˈməe̯ʔkʁəˌfõːn], "microwave" [ˈməe̯ʔkʁəːˌweːv̥], and "intracoastal" [ˌɪ̃tʃɹ̠əˈkosʲtʲɯː].