the thin hard layer that covers the outer tip of each fingerOxford Collocations Dictionaryadjectivelong,sharp,black,…verb + fingernailclip,cut,paint,…fingernail + verbdig in,scrape,grow,…fingernail + nounpolish,clippersprepositionunder the/your fingernailsSeefull entrySee related entries:Hands and nailsExtra examples‘Actually, I’m leaving you’, she said, continuing to examine her fingernails.‘Actually, I’m leaving,’ she said, examining her fingernails.I noticed I had dirt under my fingernails.She dug her fingernails into my neck.She tapped her fingernails against the table impatiently.the horrible sound of fingernails scraping across a blackboardthe sound of fingernails being dragged down a blackboard
See fingernail in the Oxford Advanced American Dictionary