| Prefix with hazard | 18 |
| Prefix with head or hole | 24 |
| Prefix with hero or matter | 26 |
| Prefix with hertz | 17 |
| Prefix with history | 19 |
| Prefix with horn or stock | 25 |
| Prefix with hydrozoline | 23 |
| Prefix with identification | 26 |
| Prefix with iliac | 17 |
| Prefix with Impressionism | 25 |
| Prefix with impressionist | 25 |
| Prefix with industry | 20 |
| Prefix with inflammatory | 24 |
| Prefix with inform | 18 |
| Prefix with information | 23 |
| Prefix with intellectual | 24 |
| Prefix with interference | 24 |
| Prefix with intestinal | 22 |
| Prefix with Iranian | 19 |
| Prefix with iron or rib | 23 |
| Prefix with jam or spam | 23 |
| Prefix with Japanese | 20 |
| Prefix with john | 16 |
| Prefix with john or god | 23 |
| Prefix with john or tasse | 25 |
| Prefix with judge or trial | 26 |
| Prefix with judicial | 20 |
| Prefix with kinetic | 19 |
| Prefix with knock | 17 |
| Prefix with knock or lock | 25 |
| Prefix with knock or nuke | 25 |
| Prefix with lace and weave | 26 |
| Prefix with lace or face | 24 |
| Prefix with lace or lock | 24 |
| Prefix with language | 20 |
| Prefix with laryngology | 23 |
| Prefix with lateral | 19 |
| Prefix with lateral and distant | 31 |
| Prefix with lateral or distant | 30 |
| Prefix with lateral or lingual | 30 |
| Prefix with lateral or state | 28 |
| Prefix with Latin | 17 |
| Prefix with law or tourist | 26 |
| Prefix with lead | 16 |
| Prefix with lead or guide | 25 |
| Prefix with lead or read | 24 |
| Prefix with leave or weave | 26 |
| Prefix with legal | 17 |
| Prefix with legal and graph | 27 |
| Prefix with legal or chute | 26 |
| Prefix with legal or medic | 26 |
| Prefix with legal or normal | 27 |
| Prefix with legal or sailing | 28 |
| Prefix with lending | 19 |
| Prefix with let or lease | 24 |
| Prefix with liberal | 19 |
| Prefix with liberal or conservative | 35 |
| Prefix with liberalism | 22 |
| Prefix with life or size | 24 |
| Prefix with life or wife | 24 |
| Prefix with light | 17 |
| Prefix with light or night | 26 |
| Prefix with light or sound | 26 |
| Prefix with like or ability | 27 |
| Prefix with liminal or national | 31 |
| Prefix with line and section | 28 |
| Prefix with line or mine | 24 |
| Prefix with lineal | 18 |
| Prefix with linear | 18 |
| Prefix with lingual | 19 |
| Prefix with lingual or lateral | 30 |
| Prefix with linguistics | 23 |
| Prefix with linguistics or pharmacology | 39 |
| Prefix with link or lock | 24 |
| Prefix with liter | 17 |
| Prefix with literal or lateral | 30 |
| Prefix with lith and plastic | 28 |
| Prefix with lithic | 18 |
| Prefix with lock | 16 |
| Prefix with lock and hero | 25 |
| Prefix with lock or knock | 25 |
| Prefix with lock or skid | 24 |
| Prefix with log | 15 |
| Prefix with log or center | 25 |
| Prefix with log or lady | 23 |
| Prefix with log or smog | 23 |
| Prefix with logic or graph | 26 |
| Prefix with logical | 19 |
| Prefix with logical or graph | 28 |
| Prefix with lope or lock | 24 |
| Prefix with loper or cede | 25 |
| Prefix with lung or marine | 26 |
| Prefix with magnetic | 20 |
| Prefix with magnetic or dynamic | 31 |
| Prefix with mall or store | 25 |
| Prefix with man or marine | 25 |
| Prefix with management | 22 |
| Prefix with mania | 17 |
| Prefix with many fruit names | 28 |
| Prefix with marathon | 20 |