expression, noun
slender character; thin handwriting
Refers to a written character or handwriting that is narrow or thin in stroke, often used when describing someone's penmanship or printed text.
彼は細い字で手紙を書いた。
He wrote the letter in slender characters.
この本は細い字で印刷されているので読みにくい。
This book is printed in thin characters, so it's hard to read.