Answer: abcdefghijklm

AnswerCrossword Clue
ABCDEFGHIJKLM

First half of a series

ABCDEFGHIJKLM

Part of a speller's repertoire

ABCDEFGHIJKLM

Part of a sequence

ABCDEFGHIJKLM
Half of a decoder ring
ABCDEFGHIJKLM
First half of things we all memorized