過労死
かろうし
karoshi
= death from overwork
過労死 (karoshi) refers specifically to death caused by work-related exhaustion — a phenomenon so embedded in Japan’s postwar labor culture that the word itself was borrowed into English unchanged. Unlike vague terms for stress or burnout, karoshi carries a precise and legally recognized meaning: a death directly attributable to excessive working hours, chronic sleep deprivation, or work-induced psychological breakdown.
過労死 describes a fatality — typically from heart attack, stroke, or suicide — that medical or labor authorities determine was caused by overwork. Japanese law defines karoshi as a labor disaster (労働災害, rōdō saigai) when the deceased worked more than 80–100 overtime hours per month in the period leading up to death, a threshold known informally as the “karoshi line” (過労死ライン). The word carries no casual register; it is used exclusively in serious, formal contexts — news reports, parliamentary debate, court proceedings, and labor advocacy. You would never use karoshi to describe feeling tired after a long week. Its closest English equivalents — “overwork death” or “death from overwork” — lack the cultural and legal weight that the Japanese term carries, which is why international media and academic papers routinely use the Japanese word directly.
Learners sometimes confuse 過労死 with 過労 (karō), which simply means overwork or chronic fatigue without implying death. Using karoshi when you mean karō risks sounding alarmist. Also note that karoshi is always written in kanji (過労死) in formal contexts; writing it in katakana (カロウシ) is unusual and may look unnatural. When reading news articles about Japanese labor reform, you will also encounter 過労死等防止対策推進法 (Karoshi Bōshi Hō), the 2014 Act on Promotion of Measures to Prevent Karoshi — knowing the compound makes the full legal term much easier to parse. Finally, karoshi is a compound noun; it does not conjugate as a verb. To say someone “died of overwork,” use 過労死する (karoshi suru) or 過労死した (karoshi shita).
過労死 is built from three kanji, each carrying precise meaning. 過 (ka) means “excess” or “going beyond a limit,” as seen in 過度 (kado, excess) and 過去 (kako, the past — time that has gone beyond). 労 (rō) means “labor” or “toil,” appearing in 労働 (rōdō, work/labor) and 労力 (rōryoku, effort). 死 (shi) means “death,” found in 死亡 (shibō, death) and 死因 (shiin, cause of death). Read together, 過労死 literally constructs the concept: death (死) from excessive (過) labor (労). The compound 過労 (karō) alone — meaning overwork or excessive fatigue — existed before karoshi entered common usage, but it was the addition of 死 that gave the phrase its stark, irreversible weight.
Everyday use
彼は毎月120時間の残業をしており、最終的に過労死した。
Kare wa mai tsuki hyaku nijū jikan no zangyō wo shite ori, saishūteki ni karoshi shita.
He was working 120 hours of overtime every month and ultimately died from overwork.
Casual / Social Media
また過労死のニュースが出た。会社は従業員の健康より利益を優先している。
Mata karoshi no nyūsu ga deta. Kaisha wa juugyōin no kenkō yori rieki wo yūsen shite iru.
There’s another karoshi story in the news. Companies keep prioritizing profit over employee health.
Formal / Cultural context
本委員会は過労死を防ぐための労働時間上限規制を早急に設けるよう求める。
Hon iinkai wa karoshi wo fusegu tame no rōdō jikan jōgen kisei wo sōkyū ni mōkeru yō motomeru.
This committee calls for the immediate establishment of working-hour caps to prevent deaths from overwork.
Karoshi emerged as a recognized social issue during Japan’s postwar economic miracle, when corporations expected employees to demonstrate loyalty through limitless working hours. The phenomenon became so widespread that by the 1980s labor lawyers and journalists had coined the term as a formal category of death. Japan’s Ministry of Health, Labour and Welfare began publishing annual karoshi reports in 2016 under the Act on Promotion of Measures to Prevent Karoshi (過労死等防止対策推進法), making Japan one of the few countries to track and report overwork deaths as a distinct public health statistic.
The legal concept of karoshi shapes how Japanese courts and labor offices assess compensation claims. If a death is certified as karoshi, the surviving family is entitled to workers’ compensation — a process that can take years and requires demonstrating that the deceased exceeded the government’s overtime thresholds. Several high-profile karoshi cases — including the 2015 suicide of a 24-year-old Dentsu employee who logged over 105 hours of overtime in one month — generated sustained media coverage and directly influenced Japan’s 2019 labor reforms, which set a legal cap of 100 overtime hours per month. Critics argue the cap itself is set dangerously close to the karoshi line, and advocacy groups such as the National Defense Counsel for Victims of Karoshi (過労死弁護団全国連絡会議) continue to push for stricter limits.