円環|えんかんenkan

1. nouncircle; ring

• SynonymリングNeutralCommon loanword in daily use for rings and circles, and also for a finger ring or a boxing ring; 「円環」 is not used for jewelry or a fighting arena.
• Synonym輪わNeutralThe most ordinary word: circles, rings, hoops, wheels; also a human circle as in 「輪に入る」. 「円環」 is the more written-style word.
• Synonym環状かんじょうNeutralRing shape, used mostly attributively as in 「環状線」 and 「環状道路」; 「円環」 refers to the ring itself.
• Synonym環形かんけいWrittenRing shape; rare even in written style, mostly in technical terms such as 「環形動物」. 「円環」 denotes the ring itself or its shape.
• Synonym輪形りんけいWrittenRing shape; rare in writing, mainly descriptive and often 「輪形の」 before a noun. Much the same meaning as 「円環」.
• Synonym環かんNeutralAlso written 「環」; identical in reading and meaning to 「輪」 — a ring or circle, far more everyday than 「円環」.
• Synonym輪っかわっかCasualColloquial and endearing: rings, loops of rope, a halo over an angel's head. 「円環」 is the written-style counterpart.

For everyday circles say 「輪」 or colloquial 「輪っか」; for finger rings or the boxing ring use 「リング」; for ring-shaped roads and lines use 「環状」. 「円環」 is written-style, describing the circular ring itself.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 丸まるい輪わ。また、そのような形状けいじょう。