comminution

The breaking or grinding up of a material to form smaller particles.

He deſcribes in a Mechanical way the manner of its Action; ſuppoſing that ſome of its Particles having undergone ſeveral Comminutions (tho not a Diſſolution) from the various Firments they have paſſed, arrive at laſt, with the Blood, at the Brain; […] thoſe of them, which are not ſmall enough to paſs thoſe Straits along with the Juice, being juſt admitted, ſtick there till other appelling Subſtances give them a farther Comminution, and ſo pretrude them along: […]

[W]hen a proportionable piece [of an aliment (food item)] is thus taken into the Mouth, the lower Jaw is variouſly mov'd by its proper Muſcles, and Maſtication is begun and carryed on by the Aſſiſtance of the Tongue, Cheeks, and Lips; the two firſt ſtill applying the leſs divided parts of the Aliment, to the Dentes Molares [molar teeth], till there's an equal Comminution of all its Parts; […]

The fracture of a bone site in multiple pieces (technically, at least three); crumbling.

Comminution of the shaft of one or of both bones of the fore-arm does not of itself indicate operative interference, other complications may necessitate primary or secondary amputation.

Wrist fractures encountered in natural disasters most frequently belong to the more complicated types, viz. III, IV and VIII. Importantly, comminutions are common. When both radius and ulnar^([sic – meaning ulna]) are involved with comminutions, joint surface involvements are often combined with soft tissue injuries.