お早うございます[ohayougozaimasu] good morning
一刻も早く[ikkokumohayaku] immediately
いち早く[ichihayaku] promptly
口早[kuchibaya] rapid talking
最早[mohaya] already

時期が早い[jikigahayai] before scheduled
時期尚早[jikishousou] premature
時機尚早[jikishousou] before its time
早手[hayate] gale
手早い[tebayai] nimble

漫ろ歩き[sozoroaruki] slow, relaxed walk
ひとり歩き[hitoriaruki] walking alone
一歩[ippo] (a) step
一歩一歩[ippoippo] step by step
一歩前進[ippozenshin] (a) step forward

横断歩道[oudanhodou] pedestrian crossing
牛歩戦術[gyuuhosenjutsu] snail's pace tactics
巨歩[kyoho] long strides
競歩[kyouho] walking race
健歩[kenpo] good walker

悪足掻き[waruagaki] useless resistance
一挙手一投足[ikkyoshuittousoku] slight effort
一足[issoku] pair (footwear)
一足[hitoashi] step
一足先[hitoashisaki] one step ahead

一足飛び[issokutobi] (at) one bound
逸足[issoku] fast runner
右足[migiashi] right foot
運動不足[undoubusoku] insufficient exercise
栄養不足[eiyoubusoku] malnutrition

逸速く[ichihayaku] promptly
音速[onsoku] speed of sound
加速[kasoku] acceleration
加速運動[kasokuundou] accelerated motion
加速度[kasokudo] acceleration

快速[kaisoku] high speed
快速電車[kaisokudensha] high-speed train
角速度[kakusokudo] angular velocity
急速[kyuusoku] rapid (e.g. progress)
減速[gensoku] deceleration