An American aquarium immortalised in the film Finding Dory has apologised for a foray into social media in which it called a large otter a “thicc girl” and an “absolute unit” in a meme-filled tweet.

California’s Monterey Bay Aquarium said sorry for using memes with “connotations we were unaware of” on its official Twitter account.

The overzealous tweet contained a slew of internet memes that commonly refer to amusingly large animals. However, some were more confusing, controversial and potentially insensitive than others.

“Abby is a thicc girl,” the tweet read. “What an absolute unit. She c h o n k. Look at the size of this lady. OH LAWD SHE COMIN. Another Internetism!”

Twenty four hours later, the aquarium apologised.

“It has come to our attention that some of the references in this tweet are problematic and insensitive,” it said. “If you follow our feed, we often reference popular memes to talk about the ocean. In this case, the memes used had connotations we were unaware of until now.”

“Thicc” (a variation of “thick”) is a positive adjective for a curvy body type that originated in African-American slang.

“Absolute unit” is a phrase applied to abnormally large people or animals, usually in the formulation: “In awe of the size of this lad. Absolute unit”.

Though coined by Twitter user @mrreptoid, it was widely publicised this year in a tweet from the Museum of English Rural Life.

Also, in this year’s New Zealand bird of the year competition, the official announcement described the winner (the kererū pigeon) as “the absolute unit, the roundest boi”.

Finally, “She chonk” and “OH LAWD SHE COMIN” both originate from the same source – a widely shared size chart that coined new names for different levels of cat fatness.

As an example, all three large animal memes frequently appeared last month when Knickers the big cow emerged.

But on Wednesday, Monterey Bay Aquarium apologised for its careless use of potentially insensitive phrases. Critics pointed out that many of the memes originated from African-American slang about women, and were inappropriate when applied to animals.

“Several terms referenced originated from African American Vernacular English (AAVE) and specifically reference black women’s bodies,” the aquarium said.

“Using them in a sea otter meme without that background makes insinuations we never intended. We need to do better.”

“We’re posting here in the thread so that people who have engaged with this tweet will join us in our learning moment.”

The not-for-profit aquarium was the first in the world to reintroduce sea otter pups to the wild. Abby, the otter in question, arrived at Monterey Bay in 2012.