內牛滿面

The idiom 淚流滿面／泪流满面 (lèiliúmǎnmiàn, “tears flowing all over one's face”) as spoken by someone speaking a Chinese dialect with n-l initial merger.

內牛滿面

1. (neologism, slang, humorous) to be so moved or excited that there are tears streaming down one's face

   小時候一直搞不懂週歲和虛歲。剛才朋友說：「週歲是從媽媽身體裡出來的時間，虛歲是從爸爸身體裡出來的時間。。」我頓時內牛滿面地懂了。。 [MSC, trad.]
   小时候一直搞不懂周岁和虚岁。刚才朋友说：“周岁是从妈妈身体里出来的时间，虚岁是从爸爸身体里出来的时间。。”我顿时内牛满面地懂了。。 [MSC, simp.]

   Xiǎoshíhòu yīzhí gǎo bùdǒng zhōusuì hé xūsuì. Gāngcái péngyou shuō: “Zhōusuì shì cóng māma shēntǐ lǐ chūlái de shíjiān, xūsuì shì cóng bàba shēntǐ lǐ chūlái de shíjiān..” Wǒ dùnshí nèiniúmǎnmiàn de dǒng le.. [Pinyin]

   I have been confused by western age and nominal age [in East Asian culture, where newborns start at the age of one year] since I was young. Just then a friend said: “Western age is when you exit mom's body, and nominal age is when you exit dad's body.” With tears streaming down my face, I suddenly understood everything.