fast on
adj.— «If I know I’ve got to be up early, I normally can’t sleep too well, but that night I was, as they say round they these parts, “fast on.” I was “fast on” and having a dream.» —“Alarming tale that gave me a wake-up call” by Ian McMillan Yorkshire Post (Leeds, United Kingdom) Jan. 29, 2008. (source: Double-Tongued Dictionary)
Further reading
A French idiom that means “to sleep in” or “lie around lazily in bed after waking” is faire la grasse matinée, literally to “make the fat morning.” If you fall in love easily, you’re said to have un coeur...
What do you call a segment of an orange? These juicy pieces of fruit go by lots of different names, including section, wedge, and carpel. But they’re also called pegs or even pigs! The stringy parts of a banana also have a surprising name...