For APA spelling, follow the following dictionaries:

Merriam Webster Dictionary
APA Dictionary of Psychology
Unabridged Edition of the Webster’s Dictionary

Pay attention to the following Latin and Greek words:

Singular / Plural

    • Appendix / Appendices
    • Criterion / Criteria
    • Curriculum / Curricula
    • Datum / Data
    • Phenomenon / phenomena

Remember to write the correct subject-verb agreement

    • The data indicate…

Use the following spelling for some common technology words:

Email              ebook              ereader             database
Data set           smartphone     internet            intranet
Wi-Fi              website            webpage          the web
Home page      username         login page       emoji/emojis  

Adapted from APA, 2020, pp.161-162

Source

The American Psychological Association. (2020).  Publication Manual of the American Psychological Association 7th edition.