das Rückgrat
backbone
The spine in humans and vertebrates, which supports the body.
Bei dem Unfall hat er sich eine Verletzung am Rückgrat zugezogen.
He suffered an injury to his backbone in the accident.

backbone
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backbone
The spine in humans and vertebrates, which supports the body.
Bei dem Unfall hat er sich eine Verletzung am Rückgrat zugezogen.
He suffered an injury to his backbone in the accident.

The word is made up of 'Rücken' (back) and 'Grat' (a sharp ridge, e.g. on a mountain). So it literally describes the central, supporting ridge of the back, which is the spine.
Das Rückgrat stützt den gesamten Oberkörper.
The backbone supports the entire upper body.
In the figurative meaning, 'Rückgrat' (backbone) is often used with verbs such as 'haben' (to have), 'zeigen' (to show), or 'beweisen' (to prove). The negative form 'kein Rückgrat haben' means that someone is spineless or cowardly.
Er hat Rückgrat bewiesen, als er seinen Fehler zugegeben hat.
He showed backbone when he admitted his mistake.
You can recognize the literal, medical meaning in the context of the body, health, and injuries. You can recognize the figurative meaning of strength of character in the context of decisions, morality, and social behavior.
Der Arzt untersuchte sein Rückgrat auf Verletzungen.
The doctor examined his backbone for injuries.
back
'der Rücken' and 'das Rückgrat' can both have to do with the rear part of the body. 'der Rücken' means the whole visible area at the back of the body. 'das Rückgrat' more specifically means the backbone or spine, the supporting part inside the back. In everyday language, 'Rücken' is much more natural when talking about sitting, carrying things, or pain. 'Rückgrat' fits better when you mean the bone structure; it also has a figurative meaning for strength of character. The words can be confused because the backbone is in the back.

Beim Training achtet die Lehrerin darauf, dass das Rückgrat gerade bleibt.
During training, the teacher makes sure that the backbone stays straight.
Er legt sich kurz hin, weil sein Rücken müde ist.
He lies down for a moment because his back is tired.