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MostThere are two common and three uncommon pronunciations of the digraph “oo”. In the early stages of the development of English, “oo” was pronounced as a long “o” (as in “floor”). The pronunciation later changed in many words, but, unfortunately, this change was not reflected in spelling.
This is usually not a problem for native speakers, who know how to pronounce words, but non-native speakers tend to mispronounce “oo” all the time. Unfortunately, there are no hard-and-fast rules for the pronunciation of “oo”, so you will just have to remember the correct variants, but there are a few patterns that may help you memorize them.
The short pronunciation
The letter group ook is mostly pronounced as [ʊk], with a short “u” as in “put” (the only exceptions are “spook” and “snooker”, which are pronounced with a long “oo”):
brook /brʊk/
cook /kʊk/
crook /krʊk/
hook /hʊk/
look /lʊk/
rook /rʊk/
rookie /ˈrʊki/
shook /ʃʊk/
took /tʊk/
The letter group ood is mostly pronounced as [ʊd], but the “exceptions” are almost as common as the “rule”: “brood”, “food”, and “mood” are pronounced with a long “oo”. Note that the symbol “(r)” below indicates an [r] that is pronounced in American English but silent in British English:
hood /hʊd/ and -hood words, e.g.:
childhood /
motherhood /ˈmʌðə(r)hʊd/
neighbourhood, neighborhood /ˈneɪbə(r)hʊd/
understood /ʌndə(r)ˈstʊd/
wood /wʊd/
The other words pronounced with a short [ʊ] are:
moor /mʊə/ UK, /mʊr/ US or /mɔː/ UK, /mɔːr/ US
poor /pʊə/ UK, /pʊr/ US or /pɔː/ UK, /pɔːr/ US
soot /sʊt/
wool /wʊl/
Finally, words derived from the words above, such as footing from foot, looked from look, etc., are also pronounced with a short [ʊ].
The long pronunciation
The vast majority of English words containing “oo” that we didn’t mention above are pronounced with a long [uː]. Here they are (exceptions to the rules mentioned above are marked with “(!)”):
boost /buːst/
boot /buːt/
brood /bruːd/ (!)
choose /tʃuːz/
cool /kuːl/
coot /kuːt/
crooner /ˈkruːnə(r)/
doom /duːm/
drool /druːl/
droop /druːp/
food /fuːd/ (!)
fool /fuːl/
hoop /huːp/
hoot /huːt/
loop /luːp/
loose /luːs/
loot /luːt/
mood /muːd/ (!)
moon /muːn/
moose /muːs/
moot /muːt/
noon /nuːn/
pool /puːl/
proof /pruːf/
root /ruːt/
school /skuːl/
schooner /ˈskuːnə(r)/
scoop /skuːp/
shoot /ʃuːt/
soon /suːn/
spook /spuːk/ (!)
spool /spuːl/
snooker /ˈsnuːkə(r)/ (!)
snooze /snuːz/
stool /stuːl/
stoop /stuːp/
tool /tuːl/
toot /tuːt/
tooth /tuːθ/
troop /truːp/
zoom /zuːm/
Furthermore, all words ending with “oo” are pronounced with a long [uː], for example,
cuckoo /ˈkʊkuː/
igloo /ˈɪɡluː/
kangaroo /ˌkæŋɡəˈruː/
loo /luː/
shampoo /ʃæmˈpuː/
taboo /təˈbuː/
tattoo /təˈtuː/
too /tuː/
voodoo /ˈvuːduː/
Finally, there are a few words for which both pronunciations, [uː] as well as [ʊ], are possible, but the variant with the long [uː] is more common, whereas the variant with [ʊ] is present only in some dialects:
groom /ɡruːm/ (less commonly /grʊm/)
hoof /huːf/ (less commonly /hʊf/)
roof /ruːf/ (less commonly /rʊf/)
roomy /ˈruːmi/ (less commonly /ˈrʊmi/)
root /ruːt/ (less commonly /rʊt/)
A somewhat special case is the word room, for which both pronunciations are common:
mushroom /ˈmʌʃruːm/ or /ˈmʌʃrʊm/
…
Other pronunciations
There are a small number of words with yet another pronunciation of “oo”. There are two words in which “oo” is pronounced as [ʌ] (as “u” in “but”):
flood /flʌd/
And several words where “oo” is pronounced as a long “o”:
floor /flɔː(r)/
moor /mɔː/ UK, /mɔːr/ US or /mʊə/ UK, /mʊr/ US
poor /pɔː/ UK, /pɔːr/ US or /pʊə/ UK, /pʊr/ US
Finally, it may happen that the two o’s in “oo” belong to different syllables. If this is the case, the first “o” is usually pronounced as “oh”, and the other one is pronounced as if the first one weren’t there, for example,
zoologist /zəʊˈɒlədʒɪst/ UK, /zoʊˈɑːlədʒɪst/ US or both with /zuː-/
coordinate /kəʊˈɔːdɪneɪt/ UK, /koʊˈɔːrdɪneɪt/ US (verb; noun with /-nət/)
microorganism /ˌmaɪkrəʊˈɔːɡənɪzəm/ UK, /ˌmaɪkroʊˈɔːrɡənɪzəm/ US
