Anniversary

Table columns:
Anniversary
Latin-derived term
Other terms
Comments

Table rows:
cells: ½ yearly
Semiannual
cells: 1 year
Annual
Paper
cells: 2 years
Biennial
Cotton
cells: 3 years
Triennial
Leather
cells: 4 years
Quadrennial
Linen
cells: 5 years
Quinquennial
Wood
cells: 6 years
Sexennial
Iron
cells: 7 years
Septennial
Wool
cells: 8 years
Octennial
Bronze
cells: 9 years
Novennial
Copper
cells: 10 years
Decennial
Tin/Aluminium
cells: 11 years
Undecennial
Steel
cells: 12 years
Duodecennial
Silk
cells: 13 years
Tredecennial
Lace
cells: 14 years
Quattuordecennial
Ivory
cells: 15 years
Quindecennial
Crystal
cells: 20 years
Vigintennial / Vicennial
China/Porcelain
cells: 25 years
Quadranscentennial
Silver jubilee
cells: 40 years
Quadragennial
Ruby jubilee
cells: 50 years
Semicentennial / Quinquagenary
Golden jubilee
cells: 60 years
Sexagennial / Sexagenary
Diamond jubilee
cells: 65 years
Sapphire jubilee
cells: 70 years
Septuagennial
Platinum jubilee
cells: 100 years
Centennial
Centenary
cells: 125 years
Quasquicentennial
Term is broken down as quasqui- (and a quarter) centennial (100 years). Quasqui is a contraction from quadrans "a quarter" plus the clitic conjunction -que "and". The term was coined by Funk and Wagnalls editor Robert L. Chapman in 1961.[2]
cells: 150 years
Sesquicentennial
Term broken down as sesqui- (one and a half) centennial (100 years)
cells: 175 years
Dodransbicentennial
Dodrans is a Latin contraction of de-quadrans which means "a whole unit less a quarter" (de means "from"; quadrans means "quarter"). 175 years is a quarter century less than the next whole (bi)century or 175 = (−25 + 200).[1]
cells: Dodrabicentennial
Alternative Latin form of Dodransbicentennial
cells: Dequasbicentennial
Alternative Latin form of Dodransbicentennial
cells: Dosquicentennial
Dosquicentennial has been used in modern times[3] and this is perhaps a modern contraction of "de-quadrans". However, it seems inappropriate to combine the terms que and de when dealing with such Roman fractions. In any event, if such a conjunction was appropriate then it would perhaps more likely have been "Dosquibicentennial" (but the result is little shorter anyway).[1]
cells: Demisemiseptcentennial
Probably[attribution needed] a modern coined term: demisemiseptcentennial; literally one-half (demi-) × one-half (semi-) × seven (sept-) × 100 years (centennial)—also demisemiseptcentenary.[4][5]
cells: Quartoseptcentennial
Probably[attribution needed] a modern coined term: quartoseptcentennial; literally one-quarter (quarto-) × seven (sept-) × 100 years (centennial)—also quartoseptcentenary.[4]
cells: Terquasquicentennial
First used by Bell Laboratories in celebrating its 175th anniversary as a corporation.[citation needed] Is a coined word for an anniversary of 175 years, but the elements of the word literally refer to an anniversary of 375 years, as follows: ter- (3) × quasqui- (1¼) × centennial (100 years)
cells: Septaquintaquinque- centennial
Suggested by lexicographer Robert L. Chapman to William Safire; first appeared in Safire's column, "On Language" (The New York Times Magazine, February 12, 1995). It is a coined word for an anniversary of 175 years, but the elements of the word literally refer to an anniversary of 35,000 years, as follows: septaquinta- (70) × quinque- (5) × centennial (100 years)
cells: 200 years
Bicentennial
Bicentenary
cells: 250 years
Sestercentennial
-
To express 2½ in Latin it would be expressed as "half-three". The term relates to being halfway [from the second] to the third integer. In Latin this is "Sestertius" which is a contraction of semis (halfway) tertius (third)—hence Sestercentennial.[1]
cells: Semiquincentennial
Probably[attribution needed] a modern coined term: semi- (half) × quin (5) × centennial (100 years) = 250 years. Used by Brown University in 2015.[6]
cells: Bicenquinquagenary
Used by Princeton University in 1996, Reading, Pennsylvania in 1998, and Washington and Lee University in 1999.[7] It is a coined word for an anniversary of 250 years: bi- (2) × cen(t)- (100) + quinquagenary (50 years).
cells: Quarter-millennial
Meaning one quarter of one thousand years.[8]
cells: 300 years
Tercentenary / Tricentenary
Tercentennial / Tricentennial
cells: 350 years
Sesquarcentennial
A modern coined term; sesquarcentennial for 350 years is deduced here from the "Sestertius" definition for 250 years above. For 350 years it relates to being halfway from the third to the fourth integer; thus a contraction of semis (halfway) and quartus (fourth); hence Sesquarcentennial.
cells: Semiseptcentennial
Probably[attribution needed] a modern coined term: semi- (half) × sept(7) × cen(t)- (100) × centennial (350 years)
cells: 400 years
Quadricentennial
Quadricentenary / Quatercentenary
cells: 500 years
Quincentenary
Quincentennial
cells: 600 years
Sexcentenary
Sexacentennial
cells: 700 years
Septcentennial
Septuacentennial
Probably[attribution needed] a coined term; earliest known use in March 1988.[9] Chiang Mai Septcentennial Stadium (Chiang Mai, Thailand) was completed in 1991.[10]
cells: 800 years
Octocentenary
Octocentennial
cells: 900 years
Nonacentennial
cells: 1000 years
Millennial
cells: 1500 years
Sesquimillennial
Term broken down as sesqui- (one and a half) millennial (1000 years)
cells: 2000 years
Bimillennial

Questions about this table:
originalText: how many years is quarter of a century
answer: answerTexts: 25 years