The story
Phono-semantic matching of Japanese カプセルホテル (kapuseru hoteru), itself a wasei eigo (和製英語; pseudo-anglicism) derived from capsule + hotel.
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A type of hotel with a number of very small "rooms" (capsules). Full definition →
Phono-semantic matching of Japanese カプセルホテル (kapuseru hoteru), itself a wasei eigo (和製英語; pseudo-anglicism) derived from capsule + hotel.
Etymology from Wiktionary, CC BY-SA 4.0.