Difference between Portmanteau Word and Singspiel

PORTMANTEAU WORD vs SINGSPIEL: NOUN

A word which combines the meaning of two words (or, rarely, more than two words), formed by combining the words, usually, but not always, by adjoining the first part of one word and the last part of the other, the adjoining parts often having a common vowel; for example, smog, formed from smoke and fog.
A new word formed by joining two others and combining their meanings

An opera in this style.
An early German form of opera consisting of spoken dialogue interspersed with song.
A dramatic work, partly in dialogue and partly in song, of a kind popular in Germany in the latter part of the 18th century. It was often comic, had modern characters, and patterned its music on folk song with strictly subordinated accompaniment.
A semidramatic work or performance in which a series of incidents are related or represented in song.
A German musical comedy of the 1700s featuring songs and ensembles interspersed with dialogue.

Abstractness, Hybridity, Metonymy, Onomatopoeic, Slanguage, Tabula, Diphthong, Lexis, Pluralized, Neologism, Folk etymology, Idiom, Noun, Blend, Portmanteau

Libretti, Claudio monteverdi, Franz lehar, Gigue, Divertimento, Recitatives, Opera seria, Incidental music, Symphonic poem, Trio sonata, Verismo, Ballade, Concerto grosso, Mozartian, Opera buffa

Bricolage, Abstractness, Hybridity, Metonymy, Onomatopoeic, Slanguage, Tabula, Diphthong, Lexis, Pluralized, Neologism, Folk etymology, Idiom, Noun, Blend

Libretti, Claudio monteverdi, Franz lehar, Gigue, Divertimento, Recitatives, Opera seria, Incidental music, Symphonic poem, Trio sonata, Verismo, Ballade, Concerto grosso, Mozartian, Opera buffa

But the word he actually used is a portmanteau word that has the feeling of both these meanings and perhaps a little more.

Vienna, Mozart transformed the buffoonery of the German singspiel to what became the foundation of German grand opera.
Mozart Singspiel as a site of what the director might call.
Singspiel, intended to encourage the composition of music dramas in German.
Ein Singspiel in vier Aufziigen aus dem Pranzosischen iibersetzt.
Singspiel in einem Aufzuge aus dem Franzosischen iibersetzt.