Going ahead or going first: acting or proceeding before others (often used as '先行する').
プロジェクトの重要な準備を先行して進めた。
We proceeded with important project preparations ahead of schedule.
新機能は一部ユーザーに対して先行して公開される予定だ。
The new feature is planned to be released early to a subset of users.
彼はいつも先行して行動するタイプだ。
He is the kind of person who always acts ahead of others.
Preceding or coming before in time or order. Used in compounds like 'preceding research' or 'pre-sale'.
論文を書く前に先行研究を丁寧に調べるべきだ。
You should carefully review preceding research before writing a paper.
この商品の先行販売は今月末から始まる。
The pre-sale of this product begins at the end of the month.
彼の考えは時代に先行していると言われた。
People said his ideas were ahead of their time.
In sports: scoring first or taking an early lead in a match.
試合序盤に相手チームが先行したが、後半で逆転した。
The opposing team took the early lead in the match, but we came back in the second half.
先行点を取って守備を固めた。
They scored first and then tightened their defense.
In horse racing: a horse that races near the front (a 'stalker' or front-running type) or the tactic of maintaining a forward position.
この馬は先行タイプで、道中は前に出て粘る走りをする。
This horse is a front-running type; it goes forward during the race and hangs on.