abecedarian
alphabetarian
apprentice
articled clerk
baby
beginner
boot
catechumen
deb
entrant
fledgling
freshman
greenhorn
greeny
ignoramus
inductee
infant
initiate
learner
neophyte
nestling
new boy
newcomer
novice
novitiate
postulant
probationer
probationist
raw recruit
recruit
rookie
tenderfoot
trainee
tyro