Example sentences
hěn很gāo高xīng兴rèn认shí识nǐ你。
Nice to meet you.
tīng听dào到zhè这gè个wǒ我hěn很gāo高xīng兴。
I'm happy to hear that.
About this word
高 is "high" and 兴 is "mood, spirits", the xìng of 兴趣 interest and 扫兴 to spoil the mood. Put together, "high spirits", which is exactly the feeling of being happy or pleased. Watch the tone: 兴 is xìng here, never the xīng of 兴奋 "excited" or 兴起 "to rise". 高兴 covers both a mood and a polite reaction, as in 我今天很高兴 "I am happy today" and 很高兴认识你 "nice to meet you". For a plainer, more casual "happy", 开心 is common in speech.
The story behind the character
高
The earliest 高 is a tall tower: a base, a body, a roof. Xu Shen wrote 高, 崇也: "lofty." A tower rising from the ground, that's tall.
兴
The earliest 兴 is four hands lifting one thing together. Xu Shen wrote 兴, 起也: "to rise." Four hands hoisting. That's 兴.