確か

• Reading: たしか
• Romaji: tashika
• Kanji breakdown: 確 (kaku/tashi) — certain, sure, reliable
• Pronunciation: /ta.ɕi.ka/

Meaning

If I remember correctly; I think; certain; definite; reliable.

Functions as both a na-adjective meaning certain/reliable (確かな情報, reliable information) and as an adverb meaning if I recall correctly (確か明日だったと思う, I think it was tomorrow). The adverbial use is extremely common in everyday conversation when recalling uncertain information. Pairs well with と思う.

Examples

1. 確か、この店は六時に閉まると思います。 If I remember correctly, I think this store closes at six.
2. 確かな情報がないと判断できません。 I can't make a judgment without reliable information.
3. 確か彼女は大阪の出身だったはずです。 I'm pretty sure she was from Osaka.

Usage Guide

Context: recollection, uncertainty, verification

Tone: tentative

Origin & History

The kanji 確 combines 石 (ishi, stone) with 隺 (kaku, a crane/bird). Stone represents solidity and certainty — something as firm and reliable as rock.

Cultural Context

Era: Classical

Generation: All ages

Social background: Universal