noun
A somewhat older or more casual word for a dictionary, especially a Japanese-language dictionary. Often used in compound words like 国語字引 (Japanese dictionary) or 漢和字引 (Kanji-Japanese dictionary). In modern Japanese, 辞書 (じしょ) is more common.
子供の頃、漢字を調べるのに字引を使っていた。
When I was a child, I used a dictionary to look up kanji.
この字
This dictionary is old, but it's still useful.
辞書 is the most common modern word for 'dictionary' and is used broadly for any language dictionary. 字引 is a more traditional or colloquial term, often implying a Japanese-language dictionary, and is less frequent in contemporary usage.
辞典 is a formal term for a dictionary or lexicon, often used in titles of reference works. It carries a more academic or comprehensive nuance compared to the casual 字引.
Compound of 字 (じ, 'character, letter') and 引 (ひき, from 引く, 'to pull, to look up'). Literally 'character lookup', referring to the act of searching for characters in a dictionary.