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one cup (of); one glass (of); one bowl (of); cupful; glassful; bowlful; spoonful
one drink (of alcohol)
full; filled (with); brimming (with); crowded; packed
fully; to capacity; to the maximum; as much as possible
a lot; much; many
all of ...; the entire ...
one (squid, octopus, crab, etc.)
one (boat)
コーヒーを一杯ください。
One cup of coffee, please.
電車の中は人で一杯だったよ。
The train was packed with people.
今日は仕事が一杯あって忙しい。
I'm busy today because there's a lot of work.