coarticulation

[ koh-ahr-tik-yuh-ley-shuh n ]
/ ˌkoʊ ɑrˌtɪk yəˈleɪ ʃən /

noun Phonetics.

concomitance of articulation, as in fro, ostensibly a succession of three discrete sounds but physically a single articulation (f-) blending into a coarticulation (-fr-), which blends into an articulation (-r-), which blends into a coarticulation (-ro-), which blends into an articulation (-o).
Also called secondary articulation. the movement during the articulation of a given sound of one or more articulators not directly involved in producing the sound.

Origin of coarticulation

First recorded in 1605–15; co- + articulation