trivial matter; ordinary thing
Almost always used in negative sentences (e.g., ただ事ではない) to mean something is not ordinary, not trivial, or serious. Rarely appears in affirmative statements.
His panic was no trivial matter.
This wound is not something ordinary. Let's go to the hospital right away.
普通 is a general adjective/noun for 'normal' or 'usual' and can be used in both positive and negative contexts. ただ事 is specifically a noun meaning 'trivial matter' and is almost exclusively used in negative constructions.
大したこと is a more colloquial expression meaning 'big deal' or 'something significant', often used in negative sentences like 大したことではない. ただ事 is more literary and formal, and emphasizes the lack of ordinariness rather than importance.
Standard mixed kanji-kana spelling; the most common written form.
Kana spelling is common in everyday writing, especially when the kanji is not needed.
Alternate kanji spelling using 只; less common but still encountered.
Rarely used kanji form.
Rarely used kanji form.
Compound of ただ (ordinary, mere) + 事 (thing, matter). The reading ごと is a rendaku form of こと. The expression has been used since classical Japanese to denote something commonplace or trivial.