the horse took off at great speed : RUN AWAY/OFF, flee, abscond, take flight, decamp, leave, go, depart, make off, bolt, take to one's heels, escape; informal split, clear off, skedaddle, vamoose.
the plane took off : BECOME AIRBORNE, take to the air, take wing; lift off, blast off.
the idea really took off : SUCCEED, do well, become popular, catch on, prosper, flourish, thrive, boom.
2192; headword