barrier

noun 0.667

supersonic

noun 0.616

language barrier

noun 0.601

speed of sound

noun 0.597

obstacle

noun 0.577

speed limit

noun 0.559

hurdle

noun 0.553

lightspeed

noun 0.551

bow shock

noun 0.546

brick wall

noun 0.546

ice barrier

noun 0.541

glass ceiling

noun 0.537

roadblock

noun 0.533

speed bump

noun 0.532

sonic boom

noun 0.531

high speed

noun 0.528

speed of light

noun 0.528

superspeed

noun 0.517

breakthrough

noun 0.515

speed

noun 0.515

windbreak

noun 0.511

soundproofing

noun 0.511

overspeed

noun 0.510

shock wave

noun 0.507

subsonic

noun 0.504

wire speed

noun 0.504

barricade

noun 0.503

barrier reef

noun 0.502