If you describe something as ludicrous, you mean that it is extremely silly, stupid, or just plain ridiculous.
When you allude to something or someone, often events or characters from literature or history, you refer to them in an indirect way.
If you collude with people, you work secretly with them to do something dishonest.
A prelude is an introduction to a musical piece or something that precedes another event.
If a fact or idea eludes you, you cannot remember or understand it; if you elude someone, you manage to escape or hide from them.
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