For non Japanese speakers meaning: number one or the absolutely first.
PS. Not that I pretend to be a speaker of the Japanese language, I have only some good notions of the language. So why do I use this word? Because Melvyn- sama (a most respectful way of addressing somebody) IS a speaker of Japanese and has lived a long time in Japan, knowing the culture, the behaviour and the Japanese food excellently vide his various grazing articles about Japanese restaurant. He is an expert.