1A colloquial, more casual alternative to する — to do, undertake, perform, play (a game), or study.
今日の宿題は誰がやるの？
Who's going to do today's homework?
週末はテニスをやる予定です。
I'm planning to play tennis this weekend.
この仕事は俺がやるよ、心配しないで。
I'll take care of this job, don't worry.
毎日30分だけでも運動をやるようにしている。
I make sure to do at least 30 minutes of exercise every day.
2To send or dispatch (something or someone) — to send off or forward to a place or person.
明日、支店に追加の在庫をやります。
I'll send additional stock to the branch tomorrow.
彼を先にやって、様子を見てください。
Send him ahead first and see how things go.
3To direct or move (one's gaze, glance, etc.) toward something — often in the set phrase 目をやる ('to glance at').
彼女は窓の外に目をやった。
She glanced toward the window.
彼はちらりと隣の席に視線をやった。
He cast a quick glance at the seat next to him.
4To give (typically to someone of equal or lower status, or to an animal) — to let have, present, or bestow.
犬に餌をやるのを忘れないでください。
Don't forget to feed the dog.
子どもにお菓子をやったら、うれしそうにしていた。
When I gave the child a snack, they looked happy.
この本、もう読まないから君にやるよ。
I'm not going to read this book again, so I'll give it to you.
5To make (a vehicle) go faster — to step on the gas (colloquial).
もう少しやって、前の車を追い越してくれ。
Speed it up a bit more and pass the car ahead.
コーナーを出たら、思い切りやってください。
Once we're out of the corner, go all out.
6To run (a business), operate a shop, or practice a profession (e.g., medicine, law) — to be engaged in as one's work.
あそこの蕎麦屋は父がやっている。
That soba shop over there is run by my father.
彼は小さな工場をやっている。
He runs a small factory.
医者をやるのは大変な仕事だ。
Being a doctor is a demanding profession.
7A colloquial way of saying to eat, drink, or smoke — e.g., 一杯やる ('have a drink'), 一服やる ('have a smoke').
仕事終わりにみんなで一杯やった。
After work, we all had a drink together.
外でたばこを一服やってくる。
I'm going outside to have a smoke.
昼にラーメンをやってから戻ります。
I'll grab a ramen at lunch and then come back.
8To hold or put on a performance — to stage an event, show, or concert (often interchangeable with 演る).
今夜、あのバンドがライブをやるらしい。
I heard that band is doing a live show tonight.
文化祭で演劇をやることになった。
We've decided to put on a play at the cultural festival.
9To ease someone's mind or console them — to relieve worry or soothe (figurative).
悩んでいる弟の話を聞いてやったら、気持ちが楽になったようだ。
I listened to my little brother's worries, and he seemed to feel more at ease.
心配しないで、僕がそばにいてやるよ。
Don't worry — I'll stay by your side to comfort you.
10Colloquially, to harm, injure, or (in extreme uses) kill — often used in threats or rough speech.
あいつを始末してやる。
I'll deal with that guy (a threat).
奴らにやられる前に、こちらからやるぞ。
Before they get us, we'll strike first.
11Vulgar slang for having sex; an explicit, colloquial expression often written in katakana as ヤる.
彼女と昨夜ヤったらしい。
Apparently he slept with his girlfriend last night.
12Intransitively, to live or get by (manage) — usually in the form やっていく, meaning to manage to keep living/functioning.
小さな町でも工夫すればやっていけるよ。
You can manage even in a small town if you put your mind to it.
彼は一人で暮らしてやっていけるのだろうか。
I wonder if he'll be able to manage living on his own.
13As a suffix attached after a verb's -masu stem, it expresses doing something completely or thoroughly (somewhat literary/dated).
彼はあの箱を放りやって、もう二度と見なかった。
He tossed that box aside and never looked at it again.
14As a suffix after a verb's -masu stem, it indicates doing something broadly or over a great distance (as in 見やる, 'to look off into the distance').
丘の上から遠くを見やると、海が見えた。
Looking out from the hilltop, I could see the sea in the distance.
彼は辺りを見やって、道を探した。
He looked around the area to find the road.
15As an auxiliary after the -te form, it means doing something for someone (typically of equal or lower status) — a rougher-sounding 'do for'.
手伝ってやるから、文句言うな。
I'll help you, so quit complaining.
黙って見てやるつもりはない。
I don't intend to just stand by and watch.
弟の宿題を手伝ってやった。
I helped my little brother with his homework.
16As an auxiliary after the -te form, it expresses making an active effort to do something — often conveying determination.
やってみせてやるから、見ていろ。
I'll show you how it's done, just watch.
絶対に成功してやるつもりだ。
I'm determined to succeed no matter what.