Botany Bay dozen
analyst
analyzer
assayer
essayer
examinant
examiner
experimenter
headpiece
helmet
inspector
investigator
observer
research worker
researcher
scrutineer
test driver
test pilot
tryer-out
visitator
visitor
teston
tizzy
asker
canopy
enquirer
inquirer
querier
questioner
instrumentation
programmer
testers
voltmeter
Chester
Esther
Hester
Kester
Leicester
Lester
Nester
Nestor
Sylvester
ester
fester
investor
jester
lester
mester
molester
nester
pester
polyester
requester
rester
semester
sequester
trimester
vester
wester