Yes it is, tongue and mother tongue as a synonym.
There is no single-word synonym for "their" in the English language.
the synonym for the word above is learing
principal
A person's 'mother tongue' is the main language that they spoke when they were growing up. Usually this will be the language which they used with their mother (which explains the name): but obviously there are exceptions to this (if your mother was a Bangladeshi immigrant who married a mid-Westerner, and you grew up in Boise, then your mother tongue is probably American English - though you might still speak some Bengali with your mother). Recent language research suggests that the main language for most people is the language they speak with their childhood friends, not the language they speak at home: so 'mother tongue' may be a misnomer. It's still a useful idea though: and one that most people understand. Your mother tongue is your first language, the language you are most at ease in , the language in your dreams.
Argot is a French, Spanish, and Catalan word meaning "slang." So I suppose the synonym would be "slang." It is also a secret language, so secret language could be another synonym for it.
There is the word 'tongue' which replaces 'language' in some contexts, such as 'mother tongue' - one's first language.
A synonym for "tongue twister" is "phrase or sentence that is difficult to articulate quickly or accurately."
lagato is an antonym and triple-tongue is a synonym.
There is no single-word synonym for "their" in the English language.
The language used in the song "Out Tongue" by Thriftworks is English.
the synonym for the word above is learing
Your "mother tongue" is your first language, the language your mother would have spoken to you as a child and that would be your natural instinctive language.
the same
principal
Language or nomenclature.
Yes.
A person's 'mother tongue' is the main language that they spoke when they were growing up. Usually this will be the language which they used with their mother (which explains the name): but obviously there are exceptions to this (if your mother was a Bangladeshi immigrant who married a mid-Westerner, and you grew up in Boise, then your mother tongue is probably American English - though you might still speak some Bengali with your mother). Recent language research suggests that the main language for most people is the language they speak with their childhood friends, not the language they speak at home: so 'mother tongue' may be a misnomer. It's still a useful idea though: and one that most people understand. Your mother tongue is your first language, the language you are most at ease in , the language in your dreams.