diff --git a/docs/phonemes.md b/docs/phonemes.md
index f0978ea0..15dd182a 100644
--- a/docs/phonemes.md
+++ b/docs/phonemes.md
@@ -61,7 +61,7 @@ transcriptions are consistent.
 
 ## Phoneme Transcription Schemes
 
-| BCP47 Tag                               | Abbreviation | Transcription Scheme                                 | Encoding |
+| BCP47 Subtag                            | Abbreviation | Transcription Scheme                                 | Encoding |
 |-----------------------------------------|--------------|------------------------------------------------------|----------|
 | `fonipa`                                | IPA          | International Phonetic Alphabet                      | Unicode  |
 | [`fonxsamp`](phonemes/xsampa.md)        | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
@@ -71,7 +71,7 @@ transcriptions are consistent.
 
 1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
    the [bcp47-extensions](https://raw.githubusercontent.com/espeak-ng/bcp47-data/master/bcp47-extensions)
-   file, so have the `x-` private use specifier before their tag names.
+   file, so have the `x-` private use specifier before their subtag names.
 
 ## Consonants
 
diff --git a/docs/phonemes/cxs.md b/docs/phonemes/cxs.md
index 80091e76..633d4b98 100644
--- a/docs/phonemes/cxs.md
+++ b/docs/phonemes/cxs.md
@@ -51,7 +51,7 @@ articulations, and diphthongs such as `ts` and consonant clusters such as
 
 ## Phoneme Transcription Schemes
 
-| BCP47 Tag                      | Abbreviation | Transcription Scheme                                 | Encoding |
+| BCP47 Subtag                   | Abbreviation | Transcription Scheme                                 | Encoding |
 |--------------------------------|--------------|------------------------------------------------------|----------|
 | [`fonipa`](../phonemes.md)     | IPA          | International Phonetic Alphabet                      | Unicode  |
 | [`fonxsamp`](xsampa.md)        | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
@@ -61,7 +61,7 @@ articulations, and diphthongs such as `ts` and consonant clusters such as
 
 1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
    the [bcp47-extensions](https://raw.githubusercontent.com/espeak-ng/bcp47-data/master/bcp47-extensions)
-   file, so have the `x-` private use specifier before their tag names.
+   file, so have the `x-` private use specifier before their subtag names.
 
 ## Consonants
 
diff --git a/docs/phonemes/kirshenbaum.md b/docs/phonemes/kirshenbaum.md
index d7c4aa44..7364a255 100644
--- a/docs/phonemes/kirshenbaum.md
+++ b/docs/phonemes/kirshenbaum.md
@@ -35,7 +35,7 @@ and `>` characters after the base phoneme (`p<dnt>`).
 
 ## Phoneme Transcription Schemes
 
-| BCP47 Tag                  | Abbreviation | Transcription Scheme                                 | Encoding |
+| BCP47 Subtag               | Abbreviation | Transcription Scheme                                 | Encoding |
 |----------------------------|--------------|------------------------------------------------------|----------|
 | [`fonipa`](../phonemes.md) | IPA          | International Phonetic Alphabet                      | Unicode  |
 | [`fonxsamp`](xsampa.md)    | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
@@ -45,7 +45,7 @@ and `>` characters after the base phoneme (`p<dnt>`).
 
 1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
    the [bcp47-extensions](https://raw.githubusercontent.com/espeak-ng/bcp47-data/master/bcp47-extensions)
-   file, so have the `x-` private use specifier before their tag names.
+   file, so have the `x-` private use specifier before their subtag names.
 
 ## Consonants
 
diff --git a/docs/phonemes/xsampa.md b/docs/phonemes/xsampa.md
index 77a7c715..0ce71ed1 100644
--- a/docs/phonemes/xsampa.md
+++ b/docs/phonemes/xsampa.md
@@ -48,7 +48,7 @@ consonant clusters such as `t-s`.
 
 ## Phoneme Transcription Schemes
 
-| BCP47 Tag                      | Abbreviation | Transcription Scheme                                 | Encoding |
+| BCP47 Subtag                   | Abbreviation | Transcription Scheme                                 | Encoding |
 |--------------------------------|--------------|------------------------------------------------------|----------|
 | [`fonipa`](../phonemes.md)     | IPA          | International Phonetic Alphabet                      | Unicode  |
 | `fonxsamp`                     | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
@@ -58,7 +58,7 @@ consonant clusters such as `t-s`.
 
 1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
    the [bcp47-extensions](https://raw.githubusercontent.com/espeak-ng/bcp47-data/master/bcp47-extensions)
-   file, so have the `x-` private use specifier before their tag names.
+   file, so have the `x-` private use specifier before their subtag names.
 
 ## Consonants