Dictionary.com presents the "most popular word" for each letter of the alphabet. These are the words, according to our logs, which were the most frequently looked-up in 2004.
| Most Popular Word | New Words Added in 2004 |
| A | affect | above the fold, actionable intelligence, areology, Ayurveda |
| B | belligerent | barrista, blog, bullet point |
| C | cynical | career coach, celebutante, cherry-pick, craft beer |
| D | democracy | dark energy, deliverable, disintermediate, drilldown |
| E | effect | empty calories, enqueue, Euroland, exoplanet |
| F | fallacious | faith-based, free climbing, future-proof |
| G | gregarious | genocide, giclée, glazomania |
| H | hyperbole | hands-free, heirloom seed, hoodie, hybrid car, |
| I | inept | identity theft, insalata verde |
| J | jealousy | job rotation, joined-up, jump the shark, junk science |
| K | knowledge | kaizen, key card, kill zone |
| L | love | laugh test, lifestyle drug |
| M | metaphor | macchiato, mash-up, modded, mojo, mouthfeel |
| N | naive | NASCAR dad, new build, Niçoise |
| O | oxymoron | on-message, ortholog |
| P | paradox | phisher, pixelated, policy wonk |
| Q | quibble | qigong, quaffable, quiddity |
| R | rhetoric | rate-capping, recipe dish |
| S | satire | scroop, skeevy, soft copy, spyware |
| T | turpitude | technology transfer, transglobal |
| U | ubiquitous | underground economy, uparmor, upsell, usability engineering |
| V | virtue | value-free, vertical writing, virtualize |
| W | www | wayfinding, wiki |
| X | xenophobia | xenotransplantation, xerostomia |
| Y | yield | yadda yadda yadda |
| Z | zeal | zaitech, zap-proof, zero-emission vehicle, zester |