慣性 is read as かんせい (kansei) and means inertia.
かんせい
kansei
かんせいもーめんと
moment of inertia
しゅうかんせい
habit-forming
かんせいけい
inertial system
かんせいこうほう
inertial navigation system
かんせいゆうどう
inertial guidance
かんせいのほうそく
law of inertia
しゅうかんせいりゅうざん
habitual abortion
しゅうかんせいやくぶつ
addictive drug
かんしゅう
becoming accustomed (to)
なれ
being used to
ならす
to accustom
なれる
to get used to doing