part of part of nail lunule of nail Wikipedia:unula_(anatomy) lunula unguis UBERON:0011190 UMLS:C0221991 A crescent-shaped whitish area of the bed of a fingernail or toenail. The lunula is the visible part of the nail matrix (i.e. the root of the nail). lunula nail lunule NCIT:C33025 SCTID:300538005 FMA:77858 integumentary system layer