rate vs spacing

Other hyponyms of rate include acceleration, deceleration, attrition rate, rate of attrition, birth rate, birthrate, fertility, fertility rate, natality, bits per second, bps, crime rate, data rate, death rate, deathrate, fatality rate, mortality, mortality rate, dose rate, erythrocyte sedimentation rate, ESR, sed rate, sedimentation rate, flow, flow rate, rate of flow, flux, frequence, frequency, oftenness, Gc, GHz, gigacycle, gigacycle per second, gigahertz, growth rate, rate of growth, cps, cycle, cycle per second, cycles/second, hertz, Hz, inflation rate, rate of inflation, jerk, knot, kc, kHz, kilocycle, kilocycle per second, kilohertz, kilometers per hour, kilometres per hour, km/h, kph, Mc, megacycle, megacycle per second, megahertz, MHz, terahertz, THz, metabolic rate, miles per hour, mph, gait, pace, heart rate, pulse, pulse rate, rate of return, rate of respiration, respiratory rate, rev, revolutions per minute, rpm, sampling rate, solar constant, speed, velocity, pace, tempo, words per minute, wpm, kilometers per second, kilometres per second, km/s.