The only normal "truly French" word I can think of that ends in o is rigolo. There is also zoo, alto, ratio.
There are also many informal or slang words that end in o, many of which are abbreviations of longer words; for example, ado, perso, diapo, homo, accro, dodo.
There are a number of abbreviations and loan words in French that end in the letter "o," such as "moto," "auto," "radio," etc. There are three common French words that are often thought to genuinely end in "o": "stylo," "lavabo," and "vélo." "Stylo," however, is a shortened form of "stylographe," "lavabo" is a loan word from Latin, and "vélo" is a shortened form of "vélocipède." To have a native word ending in "o" is simply not compatible with French orthography. This does not mean, however, that there are not words ending in an "o" sound, whether they end in the digraphs "au" or "eau" or in an "o" followed by a silent consonant. It should be remembered that "o" in French is generally pronounced as IPA [ɔ], while "au" and "eau" are pronounced as IPA [o].
Nouns ending with -o that form the plural by adding -s to the end of the word are:autoscameoskangarooskilosmemosphotospianossolosstudiostattoosvideoszoos
Some three letter words that end with "o" are:agoegoduowhowootootwoboopoomooloogoo
Some four letter words that start and end with O are:oleoOreoorzo
Five letter words that start and end with letter O are outdo and outgo.
In french, if the last letter of the word is a consonant it is only pronounced if it is in the word Careful. From that we know the -n on the end of the word will be silent. In french the letter 'e' is generally pronounced as a soft 'uh' sound. So the word would be pronounced vuh-n-o with the 'uh' and the 'o' being very soft.
How do you spell the word "word" in French? Mot! :) Word = Mot W. O. R. D. = M. O. T.
Some words that end in O are:agoalsobanjobravadobravocockatoocombocommandocuriododumbodynamoechoergoflamingogizmogogoohalohelloheroigloointokangarookazookiddokilokimonolassoloomemonoontopatiopeekaboopianopotatoradiorhinorodeososolotattoototomatotootornadotorsotriotwountovetovideovirtuosowhowooyahooyo-yozerozoo
Wacko, weirdo, whacko, whereto, whereunto, who and wino are words that begin with W. They end with O.
All musical words that end in O add an S to form the plural (altos, solos, pianos).
One example of a word in French that starts with the letter "o" is "oiseau," which means "bird" in English.
No 5 letter word in the English language starts with the letter O and ends with the letter Z.