度(たび)に is the adverbial form of the noun 度(たび), meaning 'time' (as in 'at the time of').
たびに is frequently paired with either verbs, or nouns, in order to show that something happens 'whenever (A)', or 'each time (A)'.
After nouns, the
case marking particle の will be required before
たびに.
タナカ君(くん)と飲(の)みに行(い)くたびに、二日(ふつか)酔(よ)いになる。
Every time I go out to drink with Tanaka-kun, I get a hangover.
牛乳(ぎゅうにゅう)を飲(の)むたびにお腹(なか)が痛(いた)くなる。
Every time I drink milk, I get a stomach ache.
私(わたし)は休(やす)みのたびにハワイへ行(い)きます。
Whenever I have a holiday, I go to Hawaii.
彼(かれ)は洗(あら)い物(もの)のたびに指(ゆび)を切(き)る。
Every time he does the dishes, he cuts his finger.
Like
ごとに,
たびに means 'every'. However,
たびに is most often used to convey the nuance of する
ごとに 'every time doing'. Due to this,
たびに will almost always be used to highlight some kind of action or event, rather than random amounts of time.
仕事(しごと)を休(やす)むたびに、雨(あめ)が降(ふ)って予定(よてい)が台無(だいな)しになる。
Every time I take a day off, it rains and messes up my plans.
2週間(しゅうかん)たびに、実家(じっか)に帰(かえ)る。
Every two weeks, I go to my parents house.