Lissajous figure
alternate
alternation
back and fill
back-and-forth
balance
battledore and shuttlecock
change
come and go
coming and going
cower
dither
dodder
ebb and flow
equivocate
falter
flounder
fluctuate
flux and reflux
go through phases
halt
hitch and hike
limp
lurch
metronome
oscillate
oscillator
pass and repass
pendulate
pendulum
quiver
reciprocate
reciprocation
rhythmic play
ride and tie
ring the changes
rock
rocker
rocking chair
rocking stone
see sa
seesaw
seesawing
shake
shift
shilly-shally
shuffle
shuttle
shuttlecock
move
plaything
toy
teetered
teetering
teeters
banqueting
bitching
carding
clamouring
cloudiness
counterscarp
cross-fire
dingdong
dinning
hopin'
jabbering
overexertion
parching
perfuming
plashing
riz
self-glorification
theorising
toning
twonew
Demeter
Peter
beater
cheater
depleter
dieter
eater
heater
kilometre
liter
meter
metre
neater
peter
praetor
repeater
seater
skeeter
sweeter
teter
treater