mọc sừng

Compound of mọc (“to grow”) +‎ sừng (“horn”). Semantically, compare French avoir des cornes.

• (Hà Nội) IPA^(key): [mawk͡p̚˧˨ʔ sɨŋ˨˩]
• (Huế) IPA^(key): [mawk͡p̚˨˩ʔ ʂɨŋ˦˩] ~ [mawk͡p̚˨˩ʔ sɨŋ˦˩]
• (Saigon) IPA^(key): [mawk͡p̚˨˩˨ ʂɨŋ˨˩] ~ [mawk͡p̚˨˩˨ sɨŋ˨˩]

mọc sừng

1. (idiomatic) to be cuckolded (by one's wife)/cuckqueaned (by one's husband); to be cheated on (by one's spouse)

• cắm sừng (“to cuckold/cuckquean”, literally “to stick/peg/put horns on (one's spouse)”)