Ironic and numerous are different. Humorous is synonymous with funny or amusing. - It was a humorous article about cats (it was an amusing article about cats). - It was a humorous anecdote (it was a funny story). Ironic things can be funny, but they don't have to be. It's not really about humour, it's about the situation. Irony is famously difficult to understand and many things are attributed to irony that are actually coincidence or bad luck. 1) It was ironic that he made a huge mistake in his equation, but accidentally found the right answer. 2) It was ironic that his boat was on dry land but sank when the yard flooded. The first example isn't really funny. It's just an observation of the ridiculousness of the situation. The second one is slightly funny (not for the owner, at the time at least) because it's so ridiculous that it happened that way - for the boat to sink while on land and not on the water.