Posted on November 21, 2021January 27, 2022 by Idioms Poster Mean as custard A Spoonerism of “Keen as mustard“.“Mean as custard” has a really nice ring to it. Sinister and sweet. And gloopy.From a tweet by @VoleTiny If you Spoonerise "keen as mustard" it becomes "mean as custard" which has always made me smile.— RFisken (@VoleTiny) November 19, 2021 Related IdiomsReal idiom: Keen as mustardMixed idiom: As cool as mustard Post navigationPrevious post: We have reached the pineapple of successNext post: Disappearing down a can of worms