Recently i was browsing the GC website and came to this page which i copied and paste below. It says we shouldn't use the abbreviation "SDA" in an official or public way. So my interpretation of public is when relating to non-adventists or when there are non-adventists present. If we were to use the term "SDA" casually, it would be within our adventist brothers and sisters.
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The name Seventh-day Adventist represents the Seventh-day Adventist Church, its institutions and organizations, its local churches and its members. The name and the logo are trademarked and registered identities.
As with all proper names, there are appropriate and inappropriate ways to spell, pronounce, abbreviate and otherwise use this name.
Spelling: Seventh-day Adventist, including the hyphen and a lower-case d for day.
The pronunciation: Seventh-day Ad-ven-tist with the accent on the first syllable.
The abbreviation: Adventist. Not SDA. As with most longer names, abbreviations grow out of their common use and often reflect an air of those in the know, much like contemporary slang is used. This is the manner in which SDA has come to be used in place of Seventh-day Adventist. However this usage runs counter to the purposes of a church, which is to reach out and be inclusive to all. The term SDA, out of context and without prior knowledge, can represent any number of organizations around the world, many with functions and purposes very different from the Seventh-day Adventist Church. This is why the initials SDA should never be used in any official or public way to represent the Adventist Church. The Churchs identity should always be clear and accessible.
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The name Seventh-day Adventist represents the Seventh-day Adventist Church, its institutions and organizations, its local churches and its members. The name and the logo are trademarked and registered identities.
As with all proper names, there are appropriate and inappropriate ways to spell, pronounce, abbreviate and otherwise use this name.
Spelling: Seventh-day Adventist, including the hyphen and a lower-case d for day.
The pronunciation: Seventh-day Ad-ven-tist with the accent on the first syllable.
The abbreviation: Adventist. Not SDA. As with most longer names, abbreviations grow out of their common use and often reflect an air of those in the know, much like contemporary slang is used. This is the manner in which SDA has come to be used in place of Seventh-day Adventist. However this usage runs counter to the purposes of a church, which is to reach out and be inclusive to all. The term SDA, out of context and without prior knowledge, can represent any number of organizations around the world, many with functions and purposes very different from the Seventh-day Adventist Church. This is why the initials SDA should never be used in any official or public way to represent the Adventist Church. The Churchs identity should always be clear and accessible.