hairspring

noun 0.633

mains

noun 0.623

mainsheet

noun 0.582

mainsail

noun 0.560

mainprise

noun 0.559

spring

noun 0.558

main

noun 0.550

prime mover

noun 0.546

wellspring

noun 0.544

springing

noun 0.543

mainstay

noun 0.534

spring gun

noun 0.518

motive power

noun 0.515

mainmast

noun 0.514

leading motive

noun 0.510

vital spark

noun 0.505