Answer: oncea

AnswerCrossword Clue
ONCEA... year (annually)
ONCEA.. day (vitamin dosage)
ONCEA"Christmas comes but ... year."
ONCEA... day.
ONCEA..... year (annually)
ONCEA"... Thief" (1950 movie)
ONCEA"... jolly swagman..." ("Waltzing Matilda" start)
ONCEA"... king in Narnia...": C. S. Lewis
ONCEAFirst words of "Waltzing Matilda"
ONCEA"...-Year Day" ("The Pajama Game" tune)
ONCEAFirst two words of "Waltzing Matilda"
ONCEA-- day (every 24 hours)
ONCEA'-- Thief' (John Woo film)
ONCEA-- year (annually)
ONCEA"... Thief" (1950)
ONCEA"...-Year Day" ("The Pajama Game" song)