Yod-dropping is the elision of the sound [j].

Yod-dropping before occurs in most varieties of English in the following environments:

• After [tʃ, dʒ j], e.g. chew [tʃuːz], juice [dʒuːs], yew [juː]
• After [ɹ], e.g. rude [ɹuːd]
• After consonant+[l] clusters, e.g. blue [bluː]

There are accents, e.g. Welsh English, in which pairs like chews/choose, yew/you, threw/through are distinct: the first member of each pair has the diphthong [ɪu] while the second member has [uː].

Many varieties of English have extended yod dropping to the following environments:

• After [s], e.g. suit [suːt]
• After [l], e.g. lute [luːt]
• After [z], e.g. resume [ɹɪzuːm]
• After [θ], e.g. enthusiasm [ɛnθuːziæzəm]

Yod-dropping in the above environments was formerly considered nonstandard in England, but today it is heard even among well-educated RP speakers. In General American yod-dropping is found not only in the above environments but also:

• After [t, d, n], e.g. tune [tuːn], dew [duː], new [nuː]

General American thus undergoes yod-dropping after all alveolar consonants. Some accents preserve the distinction in pairs like loot/lute and do/dew by using a fronted vowel in words where yod has been dropped, thus [luːt]/[lʉːt], [duː]/[dʉː], etc.

Some East Anglian accents extend yod-dropping not only to the position after [t, d, n], but to the position after nonalveolar consonants as well, so that pairs like pure/poor, beauty/booty, mute/moot, cute/coot are homophonous.

Related to yod-dropping is the phenomenon of yod coalescence. This is a process that occurs in almost all accents in nonstressed syllables, as in nature and pressure and occurs in some accents in stressed syllables too as in tune and dune. The process changes the clusters [dj], [tj], [sj] and [zj] into [dʒ], [tʃ], [ʃ] and [ʒ] respectively.