Spelling in APA Style papers should match the Merriam-Webster.com Dictionary. The spellings of psychological terms should match the APA Dictionary of Psychology. Thus, to determine how to spell a particular word in APA Style, first consult one of these dictionaries. The dictionary shows the proper hyphenation and capitalization to use in the word as well.
If a word appears differently in these two dictionaries, follow the spelling in the APA Dictionary of Psychology. If a word is not in either of these dictionaries, consult an unabridged edition of Webster’s dictionary. For some common technology terms, we also provide preferred spellings.
If the dictionary offers a choice of spellings, select one and use it consistently throughout your paper.
Spelling is covered in Section 6.11 of the APA Publication Manual, Seventh Edition
This guidance is the same as in the 6th edition.