diff --git a/docs/phonemes.md b/docs/phonemes.md
index 15dd182a..4670822c 100644
--- a/docs/phonemes.md
+++ b/docs/phonemes.md
@@ -67,9 +67,8 @@ transcriptions are consistent.
 | [`fonxsamp`](phonemes/xsampa.md)        | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
 | [`x-foncxs`](phonemes/cxs.md)           | CXS          | Conlang X-SAMPA                                      | ASCII    |
 | [`x-fonkirsh`](phonemes/kirshenbaum.md) |              | Kirshenbaum (ASCII-IPA)                              | ASCII    |
-| `x-fonzsamp`                            | Z-SAMPA      | Zompist Bulletin Board (ZBB) SAMPA                   | ASCII    |
 
-1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
+1. `foncxs` and `fonkirsh` 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 subtag names.
 
diff --git a/docs/phonemes/cxs.md b/docs/phonemes/cxs.md
index 633d4b98..1092490e 100644
--- a/docs/phonemes/cxs.md
+++ b/docs/phonemes/cxs.md
@@ -57,9 +57,8 @@ articulations, and diphthongs such as `ts` and consonant clusters such as
 | [`fonxsamp`](xsampa.md)        | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
 | `x-foncxs`                     | CXS          | Conlang X-SAMPA                                      | ASCII    |
 | [`x-fonkirsh`](kirshenbaum.md) |              | Kirshenbaum (ASCII-IPA)                              | ASCII    |
-| `x-fonzsamp`                   | Z-SAMPA      | Zompist Bulletin Board (ZBB) SAMPA                   | ASCII    |
 
-1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
+1. `foncxs` and `fonkirsh` 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 subtag names.
 
diff --git a/docs/phonemes/kirshenbaum.md b/docs/phonemes/kirshenbaum.md
index 7364a255..fb28999c 100644
--- a/docs/phonemes/kirshenbaum.md
+++ b/docs/phonemes/kirshenbaum.md
@@ -41,9 +41,8 @@ and `>` characters after the base phoneme (`p<dnt>`).
 | [`fonxsamp`](xsampa.md)    | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
 | [`x-foncxs`](cxs.md)       | CXS          | Conlang X-SAMPA                                      | ASCII    |
 | `x-fonkirsh`               |              | Kirshenbaum (ASCII-IPA)                              | ASCII    |
-| `x-fonzsamp`               | Z-SAMPA      | Zompist Bulletin Board (ZBB) SAMPA                   | ASCII    |
 
-1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
+1. `foncxs` and `fonkirsh` 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 subtag names.
 
diff --git a/docs/phonemes/xsampa.md b/docs/phonemes/xsampa.md
index 0ce71ed1..1cace664 100644
--- a/docs/phonemes/xsampa.md
+++ b/docs/phonemes/xsampa.md
@@ -54,9 +54,8 @@ consonant clusters such as `t-s`.
 | `fonxsamp`                     | X-SAMPA      | Extended Speech Assessment Methods Phonetic Alphabet | ASCII    |
 | [`x-foncxs`](cxs.md)           | CXS          | Conlang X-SAMPA                                      | ASCII    |
 | [`x-fonkirsh`](kirshenbaum.md) |              | Kirshenbaum (ASCII-IPA)                              | ASCII    |
-| `x-fonzsamp`                   | Z-SAMPA      | Zompist Bulletin Board (ZBB) SAMPA                   | ASCII    |
 
-1. `foncxs`, `fonkirsh`, and `fonzsamp` are private use extensions defined in
+1. `foncxs` and `fonkirsh` 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 subtag names.