| Ref. room offering | 18 |
| Ref. set | 8 |
| Ref. source | 11 |
| Ref. staple | 11 |
| Ref. staple that used to come with a magnifying glass | 53 |
| Ref. that added the word "anally" in 2010 | 51 |
| Ref. that has a zed section | 27 |
| Ref. that's been online since 2000 | 38 |
| Ref. to a prior ref. | 20 |
| Ref. to an earlier ref. | 23 |
| Ref. tome | 9 |
| Ref. tomes | 10 |
| Ref. volumes | 12 |
| Ref. wd. | 8 |
| Ref. whose last entry is "zyxt" | 41 |
| Ref. with about 22,000 pages | 28 |
| Ref. with about 600,000 word-forms | 34 |
| Ref. with more than 2 1/2 million quotations | 44 |
| Ref. with no proper nouns in its earliest edition | 49 |
| Ref. with no substitute | 23 |
| Ref. wk. | 8 |
| Ref. work | 9 |
| Ref. work chronicled in "The Professor and the Madman" | 64 |
| Ref. work featured in "The Professor and the Madman" | 62 |
| Ref. work that spans 21,730 pages | 33 |
| Ref. work that took 70 years to complete | 40 |
| Ref. work whose Compact Edition is sold with a magnifying glass | 63 |
| Ref. work with more than 300,000 entries | 40 |
| Ref. work with online subscriptions | 35 |
| Ref. works | 10 |
| Ref. works for wordsmiths | 25 |
| Ref. works sometimes sold with magnifying glasses | 49 |
| Ref. works that occupy entire shelves | 37 |
| Ref.'s cousin | 17 |
| Ref.-book word | 14 |
| Refashion | 9 |
| RefÂ’s call in boxing: abbr. | 31 |
| RefÂ’s ruling, for short | 27 |
| RefÂ's decisions, sometimes | 35 |
| Refection | 9 |
| Refer | 5 |
| Refer (back) | 12 |
| Refer (to) | 10 |
| Refer (to) indirectly | 21 |
| Refer casually | 14 |
| Refer casually (to) | 19 |
| Refer indirectly | 16 |
| Refer indirectly (to) | 21 |
| Refer indirectly to | 19 |
| Refer obliquely | 15 |
| Refer to | 8 |
| Refer to as | 11 |
| Refer to as a source | 20 |
| Refer to indirectly | 19 |
| Refer to precedent | 18 |
| Refer to, as a research paper | 29 |
| Refer to, as in a report | 24 |
| Refer to, in a footnote | 23 |
| Refer to: Lat. | 14 |
| Refer, with "back" | 28 |
| Refer, with "to" | 26 |
| Referee | 7 |
| Referee's apparel? | 22 |
| Referee's assistant | 23 |
| Referee's call | 18 |
| Referee's command before a bout | 35 |
| Referee's count | 19 |
| Referee's decision | 22 |
| Referee's demand | 20 |
| Referee's grant | 19 |
| Referee's last number | 25 |
| Referee's no-no | 19 |
| Referee's predicament? | 26 |
| Referee's ruling | 20 |
| Referee's signal | 20 |
| Referee's song to losers | 28 |
| Referee, at times | 17 |
| Referee, before a kickoff | 25 |
| Referee, slangily | 17 |
| Refereed | 8 |
| Referees ensure it | 18 |
| Referees throw them | 19 |
| Referees' needs | 19 |
| Referees, slangily | 18 |
| Reference | 9 |
| Reference a Wikipedia article, say | 34 |
| Reference abbr. | 15 |
| Reference aid | 13 |
| Reference bk. | 13 |
| Reference book | 14 |
| Reference book abbr. | 20 |
| Reference book author | 21 |
| Reference book compiler, at times | 33 |
| Reference book feature | 22 |
| Reference book for a writer | 27 |
| Reference book referral words | 29 |
| Reference book, aptly | 21 |
| Reference book, for short | 25 |
| Reference book: Abbr. | 21 |
| Reference books, often | 22 |