A team

informal

(sports) The best of a set of teams in a single club. / (informal) The group or team which performs its work most effectively; a very good team.

Japanese Meaning

（スポーツ）同一クラブ内で最も優秀とされるチーム / （口語）非常に優れたチーム、最も業績の良いチーム

A team, composed of the club's best players, will represent the club in the national cup.

一軍はクラブの主力選手で構成され、全国大会でクラブを代表します。

Sense（1）

(sports) The best of a set of teams in a single club.

The A team are playing away this Saturday.

Sense（2）

(informal) The group or team which performs its work most effectively; a very good team.

Sense（3）

(cricket, rugby) A country's reserve team or development squad, comprising the best players not selected in the national team.

He was then selected for the South African A team before making his international debut… https://web.archive.org/web/20150707130052/http://cricking.com/the-emergence-of-south-africas-black-cricketers/

A teams

（ plural ）