wisp 
/ˈwɪsp/ noun
plural wisps /ˈwɪsp/ noun [count] 1 : a thin streak of smoke, mist, etc.
▪ Wisps of steam rose up from the teapot. ▪ a wisp of smoke 2 : a thin thread or strand of something (such as hair)
▪ A few wisps (of hair) framed the sides of her face. ▪ Wisps of cotton candy clung to his mouth. 3 : a small amount of something
▪ By the morning, there was just a wisp [=bit] of snow left on the ground. ▪ There was a wisp of a smile [=a very slight smile] on her lips. 4 : a small and thin person
▪ I met her when she was just a wisp of a girl. [=a thin young girl]
▪ Wisps of steam rose up from the teapot. ▪ a wisp of smoke
▪ A few wisps (of hair) framed the sides of her face. ▪ Wisps of cotton candy clung to his mouth.
▪ By the morning, there was just a wisp [=bit] of snow left on the ground. ▪ There was a wisp of a smile [=a very slight smile] on her lips.
▪ I met her when she was just a wisp of a girl. [=a thin young girl]
— see also will-o'-the-wisp
