Nasal+plosive clusters

English has three nasal stops (m n ŋ), three voiceless plosives (p t k) and three voiced plosives (b d g). Each set consists of a labial (m p b), an alveolar (n t d), and a velar (ŋ k g) consonant. Therefore (3×(3+3)=) 18 nasal+plosive clusters should be possible. These are shown below.

The clusters in red occur only across a morpheme boundary, eg dreamt, dreamed, tomcat, home-grown, chickenpox, cranberry, pancake, downgrade, pingpong, dingbat, Washington, banged, etc. Within a morpheme only the ones in green are possible, that is, only nasal+plosive clusters where the two share their place of articulation (= are homorganic) exist within a morpheme: temper, timber, winter, panda, anchor aŋkə, finger fiŋgə.

None of these clusters occur at the beginning of words, and not all of them occur at the end of words. The following chart contains only the homorganic clusters. Those in red do not occur at the end of a word, those in green do.

It is two of the three nasal+voiced plosive clusters, the peripheral (= noncoronal) ones that are missing. Words spelled with mb or ng at their end are all pronounced with only m and ŋ at their end, respectively: eg lamb lam, climb klajm, numb nəm, bang baŋ, song soŋ, lung ləŋ, etc.^»This is the result of a change that affects most accents of English, check here for some details. Note that word-final position also occurs before suffixes that are added to words: eg lambs lamz, climbing klajmiŋ, numb­er nəmə (‘more numb’), banged baŋd, songster soŋsdə, wrongful roŋfəl, etc.^»Exceptions are the comparatives and superlatives of adjectives ending in ŋ: longer loŋgə, longest loŋgəst, stronger stroŋgə, strongest stroŋgəst, younger jəŋgə, youngest jəŋgəst. In other word-final nasal+plosive clusters, both members are pronounced: eg pump pəmp, want wont, send send, bank baŋk, etc.

This leads to contrasts like finger fiŋgə vs singer siŋə or somber (also spelled sombre) sombə vs bomber bomə (with a morpheme boundary in sing#er and bomb#er, but not in finger or somber).