TKG English Learner's Dictionary

additional

additionaladjective

American /ə.ˈdɪ.ʃə.nəl/ British /ə.ˈdɪ.ʃə.nəl/ Stress falls on the second part: uh-DISH-uh-nul.
not gradable
fairly common

  1. more than what already exists or was first planned

    not gradable [not gradable]

    Collocations

    adjective + noun additional cost, additional information, additional charge, additional time, additional support, additional staff

    Synonyms extra (the more everyday word; additional is a little more formal)

Word family

Usage

Additional is common in both speech and writing, though it is especially frequent in formal or official contexts: forms, contracts, notices, reports. Extra is the more everyday word for the same idea and often sounds a little more casual: an extra day beside an additional day.

Common mistakes

This is more additional than we need. This is more than we need.
additional is not gradable: no more additional, no very additional.

For translators

Grammar trap Additional is not gradable: say more or further, never more additional. It usually comes directly before a noun: additional cost, additional information.