1.Definition: broadly or extravagantly humorous; resembling farce
"Ludicrous green hair"
Related Adjective(s):farcical, ridiculous
2.Definition: so unreasonable as to invite derision
"It is ludicrous to call a cottage a mansion"
Related Adjective(s):absurd, cockeyed, derisory, idiotic, laughable, nonsensical, preposterous, ridiculous