Expressions (phrases, clauses, etc.), Godan verb with 'su' ending
to lead a stingy life; to scrimp and save; to pinch pennies; to light one's (finger)nails (instead of a candle)
Idiomatic expression
Also written 爪に火を灯す【つめにひをともす】、つめに火をともす【つめにひをともす】、爪に火を点す【つめにひをともす】