| y-axis | FRAK54SSPW | unknown | open | Wikidata Q26262125, MathWorld y-Axis |
| Y/y | KX25SZC9BA | unknown | out_of_scope (a notation: the notation register holds it (corpus spec K10.4)) | Wikidata Q9973, ProofWiki Symbols:Y |
| Yael Karshon | GQ0YKBSJN8 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q30336000, nLab Yael Karshon |
| Yahtzee | YEEMJF24SP | unknown | open | Wikidata Q696920, MathWorld Yahtzee |
| Yakov Perelman | RJKPGQ8NX8 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q559531, ProofWiki Mathematician:Yakov_Isidorovich_Perelman |
| Yakov Sinai | 58BGWFJ693 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q950897, ProofWiki Mathematician:Yakov_Grigorevich_Sinai |
| Yan Soibelman | ES5S7JZB9C | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q8048171, nLab Yan Soibelman |
| Yang Hui | MWC1AVQAMH | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q574521, ProofWiki Mathematician:Yang_Hui |
| Yang-Hui He | 324S8C0G0B | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q64038662, nLab Yang-Hui He |
| Yangian | 195D0VNXHR | unknown | open | Wikidata Q8048582, nLab Yangian |
| Yang–Mills existence and mass gap | 8JNH0MFS2K | statement | open | Wikidata Q1078496, ProofWiki Yang-Mills_Existence_and_Mass_Gap |
| Yang–Mills instanton | 786PEF5TPC | unknown | open | Wikidata Q55982727, nLab Yang-Mills instanton |
| Yang–Mills theory | QK9S8FPM67 | definition | open | Wikidata Q1192873, nLab Yang-Mills theory, ProofWiki Definition:Yang-Mills_Theory |
| Yasumasa Kanada | 32BGGKTYPY | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q722634, ProofWiki Mathematician:Yasumasa_Kanada |
| Yasuyuki Kawahigashi | DBRJ7PZ69X | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q11553964, nLab Yasuyuki Kawahigashi |
| Yaël Frégier | D1WXJDF10Y | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q102330338, nLab Yael Fregier |
| YBC 7289 | 8KTKQJBGXK | unknown | out_of_scope (a book, not an item of mathematics) | Wikidata Q2178529, ProofWiki Book:Tablet/YBC_7289 |
| YC9M9NXKV5 | YC9M9NXKV5 | unknown | open | Wikidata Q14737094, MathWorld ForAll |
| year | WAPQFPW6MX | definition | open | Wikidata Q577, nLab year, ProofWiki Definition:Time/Unit/Year |
| Yehoshua Bar-Hillel | 79V8EQZ7JC | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q584382, ProofWiki Mathematician:Yehoshua_Bar-Hillel |
| Yetter–Drinfeld category | C1KTC05EHK | unknown | open | Wikidata Q8053054, nLab Yetter-Drinfeld module |
| Yff center of congruence | FYEBQAAA8P | unknown | open | Wikidata Q8053398, MathWorld YffCenterofCongruence |
| Yff circles | NNDKS4XQWH | concept | open | Wikidata Q3665044, MathWorld YffCircles |
| Yiannis N. Moschovakis | C46QR5WWA2 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q92697, ProofWiki Mathematician:Yiannis_Nicholas_Moschovakis |
| yield | C7A29DTSPH | definition | open | Wikidata Q2383321, ProofWiki Definition:Yield |
| yin and yang | ZDZC5FDWPD | unknown | open | Wikidata Q62744, MathWorld Yin-Yang |
| yocto | 4Z94FCNH3Q | definition | open | Wikidata Q110823, ProofWiki Definition:Metric_System/Scaling_Prefixes/yocto- |
| Yoichiro Nambu | H1KKD5HZTC | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q188120, nLab Yoichiro Nambu |
| Yonatan Harpaz | MZP05ND2K9 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q98916880, nLab Yonatan Harpaz |
| Yoneda lemma | 1FFH34WF2A | statement | open | Wikidata Q320577, nLab Yoneda lemma, ProofWiki Yoneda_Lemma |
| Yongbin Ruan | WBBSPK2611 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q15456141, nLab Yongbin Ruan |
| Yoshio Mikami | 7KB4PGY3EC | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q251702, ProofWiki Mathematician:Yoshio_Mikami |
| yotta | MXY3P75WF2 | definition | open | Wikidata Q108474, ProofWiki Definition:Metric_System/Scaling_Prefixes/yotta- |
| Young measure | ZFYSJ9G037 | concept | open | Wikidata Q8058552, nLab Young measure |
| Young tableau | 35Z5R09MPD | unknown | open | Wikidata Q2166280, MathWorld YoungTableau, nLab Young diagram |
| Young's inequality | 6TYQBDB2BN | statement | open | Wikidata Q910563, MathWorld YoungsInequality |
| Young's lattice | CAPYW5FNCA | unknown | open | Wikidata Q932141, MathWorld YoungsLattice |
| Young–Fibonacci lattice | 1YQDDA799Q | unknown | open | Wikidata Q8058685, nLab Young–Fibonacci lattice |
| YQSQK67BMK | YQSQK67BMK | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q3710135, ProofWiki Mathematician:Tudor_Ganea |
| Yudell Luke | D6T6C8J2Y1 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q8060225, ProofWiki Mathematician:Yudell_Leo_Luke |
| Yukawa interaction | 5FVBXG4BZ8 | unknown | open | Wikidata Q31387, nLab Yukawa coupling |
| Yuli Eidelman | 8BER9JSGQV | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q112474134, ProofWiki Mathematician:Yuli_Eidelman |
| Yuli Rudyak | HRZASHZJ7S | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q8060923, nLab Yuli Rudyak |
| Yuri Golfand | 2C525BSN07 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q1713865, nLab Yuri Golfand |
| Yuri Linnik | 42JM7P6GT8 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q1384632, ProofWiki Mathematician:Yuri_Vladimirovich_Linnik |
| Yuri Manin | C4RYFV254B | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q65196, nLab Yuri Manin, ProofWiki Mathematician:Yuri_Ivanovitch_Manin |
| Yuri Matiyasevich | KBH8EA4W7B | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q707119, nLab Yuri Matiyasevich, ProofWiki Mathematician:Yuri_Vladimirovich_Matiyasevich |
| Yuri Smirnov | 25Z2JEK4MF | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q1713916, ProofWiki Mathematician:Yurii_Mikhailovich_Smirnov |
| Yuri Tschinkel | PRT0Q33228 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q2601947, nLab Yuri Tschinkel |
| Yves Laszlo | TGY15E7CJ6 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q268830, nLab Yves Laszlo |
| Yvette Kosmann-Schwarzbach | CBNEVDWAQE | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q6506935, nLab Yvette Kosmann-Schwarzbach |
| Yvonne Choquet-Bruhat | YT2EWDPH67 | unknown | out_of_scope (a person, not an item of mathematics) | Wikidata Q461112, nLab Yvonne Choquet-Bruhat |