(a) To make a rumbling sound; (b) to make a low noise; murmur, mumble, mutter; (c) of a crowd: to make noise or tumult; (d) to move with a rumbling sound; (e) to cause a rumbling sound by movement.
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(a) To be confident; also refl.; also, take heart, take courage [quot. c1384, 1st]; trusten in (of, on, to, unto, upon), have confidence in (sb., sth., oneself); rely on (sb. or sth.) for guidance……