middling
adj.of average or medium quality. You use this to describe something that is neither very good nor very bad.
adj.of moderate or average quality, size, or value. Often used to describe a person's character or a product's performance.
“The hotel was middling, nothing special but not bad.”
“The restaurant received middling reviews because the food was decent, but the service was slow and the prices were high.”
“While the protagonist is not a hero in the traditional sense, his middling nature makes him a relatable figure for the audience, as he often struggles with the same moral dilemmas faced by ordinary people.”
“This seven-core Arm chip sports the same middling GPU as last year’s G5, along with a new MediaTek modem.”
“Two “strikes” in a year might seem notable, but like the middling hurricane season to date, Arthur and Bertha were both middle-of-the road tropical storms in terms of intensity.”
The noun is probably from middle (noun) + -ing; the adjective is most likely derived from the noun, and the adverb from the adjective.
Etymology adapted from Wiktionary, available under CC BY-SA 4.0.