जो भाषा अन्य देश में बोली/समझी जाती है उसे विदेशी भाषा कहते हैं। दूसरे शब्दों में यह भी कह सकते हैं की जो भाषा उस देश में न ही बोली जाती हो न ही आधिकारिक कार्यों में प्रयोग की जाती हो उस देश के लिए विदेशी भाषा कहलाती है, जैसे रूसी भारत के लिये एक विदेशी भाषा है। पूरे विश्व में ७१०० भाषाएँ बोली जाती हैं।

A foreign language is a language that is not an official language of, nor typically spoken in, a specific country. Native speakers from that country usually need to acquire it through conscious learning, such as through language lessons at school, self-teaching, or attending language courses. A foreign language might be learned as a second language; however, there is a distinction between the two terms. A second language refers to a language that plays a significant role in the region where the speaker lives, whether for communication, education, business, or governance. Consequently, a second language is not necessarily a foreign language.