adverb:

• one by one; one after another; successively

noun:

• one clap
• one beat
• one mora (taken as a unit of time)

noun:

• century egg; thousand-year old egg; hundred-year old egg; preserved egg (Chinese delicacy) - From Chinese "pi dan"

noun:

• one edge; one end; one side ➜ 片端【かたはし】

noun:

• one hit; one drink; one toke - slang

expression / adverb:

• one by one; one after another

noun:

• being one in body and soul; of one flesh; two hearts beating as one - four character idiom

noun:

• one's parents' home - honorific language - polite language
• one's origins; one's upbringing; one's past

expression:

• burying one's head in the sand (while leaving other parts of one's body exposed); exposing one's weak point while attempting to protect oneself; hiding one's head without hiding one's bottom [literal] - idiom

noun:

• (one) matter; (one) item; (one) case

noun:

• one bunch; one bundle; one lot

noun:

• one edge; one end; one side

noun:

• mouthful; morsel; bite
• gulp; sip; draft; draught
• one word; in short
• one share; one contribution

noun:

• one-on-one fight; one-to-one fight - slang

noun:

• once in a lifetime (opportunity); (a golden opportunity that may) happen only once in a thousand years - four character idiom

noun:

• one's future; one's fate
• one's way; one's path

numeric:

• one-tenth; one percent (one-tenth of a wari); 3 mm (one-tenth of a sun); 2.4 mm (one-tenth of a mon, a traditional unit used to measure shoe sizes); 0.1 degree (one-tenth of a do, used to measure body temperature on any temperature scale)

noun:

• one-quarter of a ryou (obsolete unit of currency)
• thickness
• advantageous circumstances
• one-tenth of a monme of silver ➜ 匁【もんめ】

noun / adjectival noun:

• appropriate to one's lot in life; within one's means; fitting to one's position; suitable to one's social status - four character idiom

noun:

• selling one's personal effects in order to live (like peeling the layers of a bamboo shoot one by one)

expression / noun:

• one's just deserts; one's just desserts; one's just reward; what one deserves; come uppance

noun / adjectival noun / ~の noun:

• at one's sweet will; doing whatever one pleases; however one pleases

noun:

• one machine
• an aircraft (airplane); one aircraft
• one player (in video games)

expression:

• one must constantly be on one's guard with ...; one cannot be too careful of ...

noun:

• being once divorced; one-time divorcee; one x mark, i.e. one name struck from the koseki [literal] - humorous term ➜ 戸籍

expression / noun:

• before one's eyes; in front of one; under one's nose
• immediate; imminent; around the corner