日

What it means

What does 日 mean? It is the kanji used to denote a single calendar day or the noun 'day' in Japanese, functioning grammatically to refer to one 24‑hour period and to mark dates on schedules and timetables; it also appears in many compound words and names to signal temporal or solar-related concepts.

Main meanings

• 1. Acts as a productive morpheme in compound nouns and place names (e.g., 日本 (nihon/nippon) meaning Japan).
• 2. Serves as a common radical element that signals concepts related to light, time, or brightness in other kanji.
• 3. Has distinct on‑yomi and kun‑yomi usages that determine its pronunciation inside compounds versus in standalone words.
• 4. Appears in formal and technical vocabulary with Sino‑Japanese readings while everyday speech favors native readings and contractions.
• 5. Functions orthographically as the calendar/date marker printed on schedules, forms, and signage beyond its lexical meaning.

How to use it

Used on printed calendars and timetables to label dates; attaches to numerals to form day‑of‑month expressions where pronunciations often change irregularly; appears in compound words (formal compounds typically use on‑yomi, everyday nouns use kun‑yomi) and in proper nouns such as place and personal names; found in signage, documents, and spoken references to specific days or recurring daily phenomena in both casual and formal contexts.