
gleichbedeutend mit
synonymous with
Having exactly the same meaning; to be synonymous.
Das Wort 'Auto' ist in vielen Kontexten gleichbedeutend mit 'Wagen'.
In many contexts, the word 'Auto' (car) is synonymous with 'Wagen' (car/vehicle).
synonymous / equivalent
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synonymous with
Having exactly the same meaning; to be synonymous.
Das Wort 'Auto' ist in vielen Kontexten gleichbedeutend mit 'Wagen'.
In many contexts, the word 'Auto' (car) is synonymous with 'Wagen' (car/vehicle).

equivalent to
Having the same effect, consequence, or importance as something else; amounting to the same thing.
Eine Absage wäre für das Projekt gleichbedeutend mit dem endgültigen Aus.
A rejection would be equivalent to the final end of the project.
The word is made up of 'gleich' (same/equal) and 'bedeutend' (meaning/significant, from 'bedeuten' (to mean)). It therefore describes that two things have the same meaning.
In diesem Zusammenhang sind die beiden Begriffe fast gleichbedeutend.
In this context, the two terms are almost synonymous.
This adjective is almost always used with the preposition 'mit' and the dative. The structure is: 'Etwas ist gleichbedeutend mit etwas anderem.' (Something is synonymous/equivalent with something else.)
Ein Lächeln ist nicht immer gleichbedeutend mit Freude.
A smile is not always equivalent to joy.
When it is about words or symbols, the literal meaning (m01) is meant. When it is about actions or events, the consequences or effect (m02) are meant.
Das Wort „schnell“ ist gleichbedeutend mit „rasch“.
The word 'schnell' (fast) is synonymous with 'rasch' (quickly).
In this meaning, a negative or drastic consequence is often emphasized. It describes that an action has the same result as another, often worse event.
Den Vertrag nicht zu unterschreiben, ist gleichbedeutend mit einer Kriegserklärung.
Not signing the contract is equivalent to a declaration of war.
synonym
Synonym and gleichbedeutend can describe the same linguistic relationship. Synonym refers to one word serving as a substitute for another, while gleichbedeutend can also describe statements with the same effect or consequence. Use Synonym for individual words; for statements or consequences that are the same, gleichbedeutend is also appropriate.

Die beiden Aussagen sind für den Leser gleichbedeutend.
The two statements are equivalent for the reader.
„Beginnen“ ist ein Synonym für „anfangen“.
“Beginnen” is a synonym for “anfangen”.