A favorable moment or opening to do something; common in written and news-style Japanese, especially in phrases such as 好機を逃す and 好機と見る.
He did not miss the chance and started a new business.
Now is the right opportunity to put the plan into action.
He seized the opportunity and launched a new business.
I was fortunate to have the opportunity to study abroad.
He took his retirement as an opportunity to move abroad.
チャンス is a casual, everyday loanword for 'chance,' whereas 好機 is more formal and typical of written or news-style Japanese.
時機 focuses on the right timing or moment to act, while 好機 emphasizes the favorable opportunity itself.
好機 names a good chance directly and concretely, while 機運 is more formal and stresses the ripening circumstances that make the chance possible.
好機 is a more formal, neutral word for a favorable opportunity, while 潮時 implies timing tied to a natural flow, often with a sense of inevitability about ending or changing something.
好機 stresses a favorable chance worth seizing, while 時宜 focuses on the correctness of the timing itself rather than the opportunity.
好機 is a formal word for a favorable opportunity, while 隙 keeps the sense of a fleeting opening that must be seized quickly.
好機 (a good opportunity) and 光輝 (brightness, splendor) are pronounced identically as こうき but have completely unrelated meanings.
A Sino-Japanese compound: 好 means 'good' or 'favorable,' and 機 means 'occasion, opportunity, or turning point.' This is a component-based explanation of the spelling, not a detailed historical derivation.