4-letter words that end in o
- trio — a musical composition for three voices or instruments.
- tvro — television receive only: an antenna and associated apparatus for reception from a broadcasting satellite
- typo — typographical error.
- tyro — a beginner in learning anything; novice.
- ucho — (audio, software) (Polish for "ear") A program by Stanislaw Raczynski for analysing wav audio files to determine which musical notes are sounding at each instant. UCHO can output the results as a MIDI file.
- umbo — a boss on a shield, as one at the center of a circular shield.
- unco — remarkable; extraordinary.
- undo — to reverse the doing of; cause to be as if never done: Murder once done can never be undone.
- unto — to (in its various uses, except as the accompaniment of the infinitive).
- updo — a hairdo that is combed or brushed up, away from the face.
- upgo — to ascend or go up (something)
- upto — United Power Trades Organization
- urao — a type of mineral with the formula Na2CO3·NaHCO3·2H2O
- uspo — United States Post Office
- vego — vegetarian
- veto — the power or right vested in one branch of a government to cancel or postpone the decisions, enactments, etc., of another branch, especially the right of a president, governor, or other chief executive to reject bills passed by the legislature.
- vico — Giovanni Battista [jaw-vahn-nee baht-tees-tah] /dʒɔˈvɑn ni bɑtˈtis tɑ/ (Show IPA), 1668–1744, Italian philosopher and jurist.
- vigo — Jean [zhahn] /ʒɑ̃/ (Show IPA), (Jean Almereyda) 1905–34, French film director.
- vino — wine; specifically, red Italian wine, as chianti.
- viso — Mount, a mountain in NW Italy: highest peak of the Cottian Alps. 12,602 feet (3841 meters).
- vito — a male given name.
- vivo — with life and vigour
- vslo — Victoria Shamrocks Lacrosse Organization
- waco — a city in central Texas, on the Brazos River.
- wako — Wisconsin Area Killifish Organization
- wbbo — World Black Belt Organization
- wcbo — World Chess Boxing Organization
- wcwo — West Coast Wrestling Officials
- wero — the challenge made by an armed Māori warrior to a visitor to a marae
- wgpo — Word Game Players Organization
- whoo — An expression of delight.
- wiho — Womens Ice Hockey Organisation
- wino — a person who is addicted to wine, especially a derelict.
- wipo — World Intellectual Property Organization
- wito — Women In The Outdoors
- wmto — World Muay Thai Organization
- wnso — World Natural Sports Organization
- wppo — Western Pennsylvania Paintball Organization
- wsko — World Shorinji Kempo Organization
- xiao — Type of Chinese flute.
- xoxo — An abbreviation for hugs and kisses, usually placed at the end of a letter.
- xylo — (colloquial, rare) xylophone.
- yafo — Jaffa.
- yayo — (US, slang) cocaine.
- yebo — an expression of affirmation
- yedo — a former name of Tokyo.
- yezo — former name of Hokkaido.
- yoho — to shout “yo-ho!”.
- yolo — to engage in impulsive or reckless behavior with this sort of rationalization: We’ve been YOLOing all night.
- yoyo — a spoollike toy consisting of two thick wooden, plastic, or metal disks connected by a dowel pin in the center to which a string is attached, one end being looped around the player's finger so that the toy can be spun out and reeled in by wrist motion.