meek mild boring. Also humourless uninteresting unexciting.
The word inoffensive is an adjective. It describes something that is not offensive.
there was an inoffensive article in the newspaper that the man loved.
the root word is dull
Dull?
Another word for dull and boring would be gloomy.
To use the word "dull" in a sentence, you could say: "The lecture was so dull that I struggled to stay awake."
You don't, because there is no such word. Perhaps you are thinking of "inoffensive," which is the opposite of "offensive." Something that is "offensive" offends (bothers, upsets, annoys) other people. The racist remarks made by the owner of the Los Angeles Clippers were considered so offensive that people demanded that he resign. As for "inoffensive," you use it like this: The comedian sometimes was very sarcastic, but his jokes were generally inoffensive, so nobody complained about him.
This word dull is not adequate here.
The knife is to dull to cut anything.
Dull can be used as an adjective and a verb.
Inoffensive means not likely to offend or upset someone. It describes something that is not provocative, harmful, or controversial.
"The sky is looking dull today." "Talking to Joe is really dull." "Mary finds maths dull."