we call all langguages rare foreign languages except chinese and english,

direct translation is "minority language". But the definition is hard to define. Sometimes, it is regional / cultural dependent. However, definitely, some common languages such as English, French, German, Russian, Spanish, Portuguese, Japanese, Korean, Chinese..... are not minority language for sure. If a language is considered as "小语种", the translation service cost is usually VERY expensive.

就是tukkk，http://baike.baidu.com/view/89713.htm?fr=aladdin#1

"小語種" 這個詞似是流行於中國境內 台灣人沒這麼用 "小語種" 其實就是 "非國際通用語言" 何謂 "小語種" ? 沒有公認的定義 你可以說是 聯合國目前 6種 通用工作語言 ( 即英語、漢語、法語、俄語、西班牙語、阿拉伯語等) 之外的其他語言 你也可以說是 italki 12種 popular languages 以外的其他語言 Popular languages English 133179 question(s) Chinese (Mandarin) 14599 question(s) Korean 14270 question(s) Japanese 11232 question(s) Spanish 10848 question(s) French 10794 question(s) German 9874 question(s) Italian 8545 question(s) Arabic 5345 question(s) Russian 4792 question(s) Portuguese 2188 question(s) Hindi 1133 question(s)