Weight (20-volume set)62.6 kg
3.5 tenthsMale gorillas
554Sticks of butter
About 138 pounds
The world's least useful encyclopedia

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Every word in English, plus the ones English stole/Literature & Writing
The Oxford English Dictionary (OED) is the definitive historical dictionary of the English language. The full second edition contains 21,728 pages in 20 volumes, defines 291,500 entries, and includes 2.4 million quotations. It took over 70 years to complete the first edition. The word with the longest entry is 'set,' with over 430 senses.
About 138 pounds
About 4.5 feet
About 540 MB digitized
20 volumes stacked
70 years (1858-1928)