High or tall (physical height or elevation).
富士山は日本で一番高い山だ。
Mount Fuji is the tallest mountain in Japan.
あのビルはとても高いので、上の階は景色がいい。
That building is very tall, so the upper floors have a good view.
彼は身長が高いからバスケットが得意だ。
He's tall, so he's good at basketball.
Expensive; costing a lot of money.
この時計は高くて買えない。
This watch is too expensive for me to buy.
最近、物価が高いので節約しないといけない。
Lately prices are high, so we have to save money.
品質が高い分、値段も高い。
Because the quality is high, the price is also high.
High in level or degree; above average in quality, skill, or rating.
彼の技術は非常に高いと評価された。
His skill was evaluated as very high.
この学校は進学率が高い。
This school has a high advancement rate.
期待が高いプレッシャーを感じる。
I feel the pressure of high expectations.
Loud (often used for voice or tone being strong/noticeable). Note: volume is more commonly expressed with 大きい.
彼はいつも声が高くて遠くまで聞こえる。
His voice is always loud and can be heard from far away.
あのアナウンサーは声が高くて元気に聞こえる。
That announcer's voice sounds lively because it's loud/high.
High-pitched; having a high pitch (voice or sound).
猫の鳴き声は高い音だ。
A cat's meow is a high-pitched sound.
彼女は高い声で歌うのが得意だ。
She's good at singing in a high register.
その楽器は音が高すぎて耳に痛い。
That instrument's sound is so high-pitched it hurts the ears.