Antonyms for the word "billboarded" include understated, subtle, discreet, and restrained. These words convey the opposite of the loud and bold nature of billboarded advertisements. Understated ads use a less aggressive approach, while subtle ads suggest the message indirectly. Discreet ads are designed to blend in with the environment, while restrained ads feature a minimalist design that doesn't shout for attention. These antonyms generally appeal to a more sophisticated and discerning audience. Advertisers use different approaches to reach their target audience, and choosing the right one depends on the product, target market, and overall marketing goals.