Originally stolen from Wikipedia but since much expanded by me.
ANA – All Nippon Airlines
Asahi – Morning light
Bridgestone — named after founder Shojiro Ishibashi. The surname Ishibashi (ﾎｴ) means “stone bridge”, or “bridge of stone”.
Canon — Originally (1933) Precision Optical Instruments Laboratory. The new name (1935) derived from the name of the company’s first camera, the Kwanon, in turn named after the Japanese name of the Buddhist bodhisattva of mercy. (In Japanese it is still always pronounced with the first sounds as kya- kyanon)
Casio — from the name of its founder, Kashio Tadao, who had set up the company Kashio Seisakujo as a subcontractor factory. (In Japanese it is usually pronounced with sh sound- Cashio- as the sounds si and shi are indistinguishable in Japanese).
Daihatsu — shortened from 大阪の発動機製造 Osaka motor production and it got shortened to 大発 – Daihatsu (Great development), as dai is another pronunciation for the O in Osaka.
Datsun — first called DAT, from the initials of its financiers Den, Aoyama and Takeuchi. Soon changed to DATSON to imply a smaller version of their original car, then (as SON can means “loss” in Japanese) again to DATSUN when they were acquired by Nissan.
Dentsu – Electronic communication (because it used to be a telegraph company)
Epson — Epson Seiko Corporation, the Japanese printer and peripheral manufacturer, was named from “Son of Electronic Printer”
Fujitsu – Short for Fuji Tsūshinki Seizō (Fuji – after the mountain – telecommunications equipment manufacturing)
Hard Off- It is a second hand hardware store in the same chain as Book Off (“off” suggesting cheapness), but not a chain that will be expanding abroad unless it takes a huge change in product range, I think…
Hitachi — old place name, literally “sunrise”
Honda — from the family name of its founder, Soichiro Honda (Honda is a common name, with the first kanji “Hon” meaning root or base, and the second kanji “da” meaning rice field).
JAL — from Japan Airlines
JR – Japan Railways
JVC — Japan Victor Company
Kawasaki — from the name of its founder, Shozo Kawasaki (Kawasaki is a very common family name that comes from the kanji “Kawa” meaning river and “saki” meaning cape, which explains why Kawasaki the company has no connection to Kawasaki the much ignored city between Yokohama and Tokyo).
Kirin – Giraffe, and the mythical Chinese creature which shares its name.
Komatsu — Japanese construction vehicle manufacturer named from the city of Komatsu, Ishikawa, where it was founded in 1917.
Konica — it was earlier known as Konishiroku Kogaku. Konishiroku in turn is the short for Konishiya Rokubeiten which was the first name of the company established by Rokusaburo Sugiura in the 1850s
Korg — named from the surnames of the founders, Tsutomu Katoh and Tadashi Osanai, combined with the letters “rg” from the word organ.
Kyocera — from Kyoto Ceramics, after Kyoto in Japan.
Mazda Motor Corporation — the company was founded as Toyo Kogyo, started manufacturing Mazda brand cars in 1931, and changed its name to Mazda in 1984. The cars were supposedly named after Ahura Mazda, the chief deity of the Zoroastrians, though many think this explanation was created after the fact, to cover up what is simply a poor anglicized version of the founders name, Jujiro Matsuda. This theory is supported by the fact that the company is referred to only as “Matsuda” in Japan.
Mitsubishi — the name Mitsubishi has two parts: mitsu means three and hishi (changing to bishi in the middle of the word) means diamond (the shape). Hence, the three diamond logo. (Note that “diamond” in this context refers only to the rhombus shape, not to the precious gem.)
Mitsui – Three wells
Mizuho – abundant rice, from an ancient name for Japan “豊葦原の瑞穂の国 (とよあしはらのみずほのくに)’ Toyoashihara no mizuho no kuni’.
Mos Burger – Mountain Ocean Sky, apparently
MUFG – Mitsubishi UFJ Financial Group
NEC – Nippon Electric Company
NHK – Nippon Hoso Kyokai (Japan Broadcasting Organisation).
Nikkei – Nihon Keizai Shimbun (Japan Economics Newspaper)
Nikon — the original name was Nippon Kogaku, meaning “Japanese Optical”. There is still a “Kogaku street” in Oimachi, Tokyo to one of their factories.
Nintendo – According to a book on the company, the word “Nintendo” means “leave luck to heaven” or “We do what we can” which suggests the chance inherent in card games, their first products.
Nissan — the company was earlier known by the name Nippon Sangyo which means “Japanese industry”.
Nissin – 日清, which looks like it might mean “Japanese pickles”
Nomura – A common family name meaning “field village”
NTT – Nippon Telegraph and Telephone
Ricoh – Riken Kankoshi – Riken Sensitised Paper – (Riken means something like “scientific research”)
Sansui – Mountain + water
Sanyo — meaning three oceans in Japanese.
SEGA — Service Games of Japan was founded by Marty Bromley (an American) to import pinball games to Japan for use on American military bases.
Seiko —from Seikosha (精工舎), roughly “House of Exquisite Workmanship”
Sharp — Japanese consumer electronics company named from its first product, an ever-sharp pencil (mechanical pencil/ automatic pencil), still called “sharp pen” in Japanese after that product.
SMBC – Mitsubishi Sumitomo Banking Corporation (no idea why the first two words are reversed in the acronym)
Sony — from the Latin word ‘sonus’ meaning sound, and ‘sonny’ a slang word used by Americans to refer to a bright youngster, “since we were sonny boys working in sound and vision”, said Akio Morita. The company was founded as Tokyo Tsoshiu Kogyo KK (Tokyo Telecommunications Engineering Corporation) in 1946, and changed its name to Sony in 1958. Sony was chosen as it could be pronounced easily in many languages.
Subaru — from the Japanese name for the constellation known to Westerners as Pleiades or the Seven Sisters. Subaru was formed from a merger of seven other companies, and the constellation is featured on the company’s logo.
Sumitomo – The kanji mean “live” and “friend”. “The Sumitomo group traces its roots to a bookshop in Kyoto founded circa 1615 by a former buddhist priest, Masatomo Sumitomo.”
Suzuki — from the name of its founder, Michio Suzuki. Suzuki is the most popular Japanese family name and means “bell tree”.
TDK – Tokyo Denki Kagaku Kokyo (Tokyo Electric Chemicals)
Toshiba – A combination of the first syllable of Tokyo and the first word of “Shiba ura” (an area in Tokyo), from the names of the two companies that merged to create that company
Toyota — from the name of the founder, Sakichi Toyoda. Initially called Toyeda, it was changed after a contest for a better-sounding name. The new name was written in katakana with eight strokes, a number that is considered lucky in Japan.
Yakult – from the Esperanto word for yoghurt (thanks to a commenter for this one)
Work in progress
Kao – 花王 – flower king???
Kanebo – Always written in katakana, so can’t find the original meaning
Shinseido – 資生堂 – “The name ‘Shiseido’ comes from Chinese Yi Jing, the Book of Changes from the Four Books and Five Classics of Confucianism.” according to their website, but doesn’t explain why or what it means
Hina Daiichi Sankyo Dentsu Hakuhodo Odakyu
JCB credit cards
And requests gratefully accepted.