Definition of grave
- graved the dates of his birth and death on the headstone
This violation of school rules is a grave matter.
His carelessness could have grave consequences.
They have placed themselves in grave danger.
I have grave doubts about this plan.
suffering from a grave illness
The judge issued his ruling with a grave expression.
The French word père is written with a grave accent over the first e.
Gravity has a familiar physical meaning but also a nonphysical meaning—basically "seriousness". Thus, something grave possesses gravity. You can refer to the gravity of a person's manner, though public figures today seem to have a lot less gravity than they used to have. Or you can talk about a grave situation, as in the example sentence. But even though Shakespeare makes a pun on grave when a dying character talks about being buried the next day ("Ask for me tomorrow and you shall find me a grave man"), the word meaning "hole for burying a body" isn't actually related.
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