dictionary
Pronunciation: /ˈdɪkʃ(ə)n(ə)ri/
noun ( plural dictionaries)

Origin:
early 16th century: from medieval Latin dictionarium (manuale) or dictionarius (liber) 'manual or book of words', from Latin dictio (see diction)

Spelling help
Remember that dictionary is spelled with -ar- after the n.

a dictionary is an alphabetical reference book.