Unterbau
base course
base with pivoting support
base
bed
body plies
body ply cord
body substructure
bottoming
carcass
casing
chassis
earthfill
embankement
embankment
fill
floor assembly
foundation course
foundation
foundations
road-bed
running gear
sub-base
sub-grade
sub-struction
sub-structure
subbase
subframe
substratum
substructure
supporting structure
tire body
track bed
under planting
underbody
undercarriage
underframe
understructure