I used 'mother tongue' to describe in conversation my first language.
Are there any terms that are used formally or informally to specifically refer to someone's second language?
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Sign up to join this communityI used 'mother tongue' to describe in conversation my first language.
Are there any terms that are used formally or informally to specifically refer to someone's second language?
Second language is a good term.
I have often seen target language too to speak about the language you are currently learning, but only when you're speaking about learning the language.
For English speakers:
While often referred to as the " mother tongue / language you know / first language / known language " these terms may be called "source language" in this case.
in this case L2 is standing for "Language 2" or "additional language". Where this terminology is used " mother tongue / language you know / first language / known language " is usually referenced by L1.
This terminology is also useful if you are wishing to refer to further languages being learned/known/referred to. ie. "They are learning L2 through their knowledge of L3." Where L3 is another language to L1 (first language) that they have already learned.