مَضْحَكٌ

[ lit. A place of laughing: the front teeth; because they appear in laughing; like مَبْسِمٌ: plural مَضَاحِكُ.] One says, بَدَتْ مَضَاحِكُهُ and ↓ ضُحْكَتُهُ and [in like manner] مَبَاسِمُهُ (assumed tropical:) [His front teeth appeared, by his laughing]. (TA.)