Translation guide
The English word "phase" has several distinct meanings. This guide covers the most common uses for learners: a stage in a process, a temporary state or period, and the scientific/technical sense of a distinct form of matter or a synchronized part of a cycle.
Referring to a distinct period or step within a development, project, or sequence.
The most common and versatile word for a stage, step, or phase in a process. Used in both formal and everyday contexts.
プロジェクトは次の段階に入った。
The project has entered the next phase.
この計画は三つの段階に分かれている。
This plan is divided into three phases.
Used for a phase or aspect of a situation, often in more abstract or strategic contexts (e.g., a new phase in a conflict or game). Slightly more formal than 段階.
交渉は新たな局面を迎えた。
The negotiations have entered a new phase.
A direct loanword from English, commonly used in business, IT, and project management. Sounds modern and technical.
第一フェーズは来月完了予定です。
The first phase is scheduled to be completed next month.
Often used as a suffix to indicate a defined period or phase, such as in 第一期 (first phase/term). Common in formal planning and historical contexts.
工事は第一期が終了した。
The first phase of construction has been completed.
Describing a passing stage in life, behavior, or a condition, often implying it will change.
A natural way to say something is 'just a phase' or temporary. Often used with ～に過ぎない (is nothing more than).
それは一時的なものに過ぎないよ。
It's just a phase.
反抗期も一時的なものだ。
The rebellious phase is also temporary.
Refers to a period or time, often used for phases in life or development. More general than 段階.
思春期は難しい時期だ。
Adolescence is a difficult phase.
Means 'period' or 'term', emphasizing duration. Can be used for a phase with a set timeframe.
Referring to a distinct form of matter (solid, liquid, gas) or a synchronized stage in a wave, signal, or cycle.
The standard scientific term for a phase of matter or a phase in a physical/chemical system. Also used in mathematics.
水は温度によって液相、固相、気相に変化する。
Water changes into liquid phase, solid phase, and gas phase depending on temperature.
Specifically means 'phase' in the context of waves, signals, or oscillations (e.g., phase shift). Technical term.
Also used in technical fields as a direct loanword, especially in engineering and computing.
While フェーズ is widely understood in business and tech, using it in everyday conversation about life stages or simple processes can sound unnatural or overly technical. Stick to 段階 or 時期 for general use.
段階 implies a step-by-step progression (like stairs), while 局面 focuses on the state or aspect of a situation at a given moment, often in competitive or strategic contexts. Use 段階 for sequential phases and 局面 for situational phases.
This period is an experimental phase.
This circuit adjusts the phase.
The signal's phase is off.