circuit

Compared meaning: a trip visiting several places (noun).

比较义项：巡回旅行、环行路线（名词）。

• tour

  General term for a trip visiting several places, often for sightseeing or business; it does not need to loop back to its starting point.

  泛指到访多个地方的旅行，多用于观光或出差，不必绕一圈回到起点。

  We took a tour of the old castle last weekend.

  上周末，我们游览了那座古老的城堡。

• circuit 本词

  A route or round of visits that loops back to its starting point, often a fixed track or a professional round such as a judge's circuit, rather than a casual sightseeing trip.

  指绕一圈回到起点的路线或巡回，常用于固定赛道或法官巡回审判等职业性活动，而非一般的观光旅行。

  The runners completed one circuit of the track before the final sprint.

  赛跑者们在最后冲刺前绕跑道跑了一圈。

Tour and circuit mean a trip visiting several places. Tour is the general word for sightseeing or business, without returning to its start. Circuit describes a route looping back to its start, like a racetrack or a judge's circuit. Circuit's electrical sense is not compared.

这两个词在“巡回旅行、环行路线”这个意义上很接近，但侧重不同：tour 泛指到访多个地方的旅行，多用于观光或出差；circuit 强调绕一圈回到起点，常见于职业巡回、固定赛道或法官巡回审判等场合。这里不比较 circuit 的“电路”等其他义项。