diff --git a/docs/developer_docs/contributing/howtos.md b/docs/developer_docs/contributing/howtos.md
index 405a6311c35..438f25690f6 100644
--- a/docs/developer_docs/contributing/howtos.md
+++ b/docs/developer_docs/contributing/howtos.md
@@ -342,6 +342,12 @@ uses Claude AI to generate draft translations for any missing entries. All
 AI-generated strings are marked `#, fuzzy` and tagged with an attribution
 comment so that human reviewers know they need to be checked before merging.
 
+The script never touches entries that must stay literal — msgids in its curated
+`DO_NOT_TRANSLATE` set (icon names, enum values, SQL keywords, API field names,
+example placeholders) and any entry carrying an explicit do-not-translate
+translator comment (e.g. the ru catalog's `# Не переводить`). Those are left
+untranslated so they fall back to the source token.
+
 #### Prerequisites
 
 ```bash
diff --git a/scripts/translations/backfill_po.py b/scripts/translations/backfill_po.py
index 25eed9ed444..b5cbffd0c4e 100644
--- a/scripts/translations/backfill_po.py
+++ b/scripts/translations/backfill_po.py
@@ -152,6 +152,60 @@ def _is_missing(entry: polib.POEntry) -> bool:
     return not entry.msgstr
 
 
+# msgids that must never be machine-translated: literal tokens compared against
+# source (SQL keywords, confirmation words), enum values (d3 interpolation
+# modes), icon names (e.g. "bolt" -> the ⚡ Explore control icon), API field
+# names, code constants, and example placeholders. Seeded from the
+# "# Не переводить" (do-not-translate) markers a human translator curated in the
+# ru catalog; these strings are language-independent, so the set applies to
+# every catalog. Translating them can break icon lookups, enum matching, or API
+# contracts, or is simply meaningless (proper nouns, example values).
+DO_NOT_TRANSLATE: frozenset[str] = frozenset(
+    {
+        "10000",
+        "DELETE",
+        "ECharts",
+        "EMAIL_REPORTS_CTA",
+        "GROUP BY",
+        "NOT GROUPED BY",
+        "OVERWRITE",
+        "TEMPORAL_RANGE",
+        "WFS",
+        "WMS",
+        "XYZ",
+        "bolt",
+        "crontab",
+        "error_message",
+        "pivoted_xlsx",
+        "schema1,schema2",
+        "sql",
+        "step-after",
+        "step-before",
+        "superset.example.com",
+        "your-project-1234-a1",
+    }
+)
+
+# Translator comment (in any catalog) explicitly marking an entry off-limits,
+# e.g. the ru catalog's "# Не переводить". Honored so a human translator's
+# deliberate decision to leave a string untranslated is never overridden.
+_DO_NOT_TRANSLATE_COMMENT = re.compile(
+    r"не\s+переводить|do[\s-]?not[\s-]?translate|don'?t\s+translate",
+    re.IGNORECASE,
+)
+
+
+def _is_do_not_translate(entry: polib.POEntry) -> bool:
+    """Return True if an entry must be left for a human (never machine-filled).
+
+    Either its msgid is in the curated DO_NOT_TRANSLATE set, or a translator
+    comment explicitly marks it do-not-translate.
+    """
+    if entry.msgid in DO_NOT_TRANSLATE:
+        return True
+    return bool(entry.tcomment and _DO_NOT_TRANSLATE_COMMENT.search(entry.tcomment))
+
+
 def _context_langs(
     item: dict[str, Any], index: dict[str, Any], target_lang: str
 ) -> list[str]:
@@ -647,6 +701,15 @@ def backfill(
     missing: list[polib.POEntry] = [e for e in cat if e.msgid and _is_missing(e)]
     print(f"Found {len(missing)} untranslated entries for '{lang}'.", file=sys.stderr)
 
+    skipped_dnt = [e for e in missing if _is_do_not_translate(e)]
+    if skipped_dnt:
+        missing = [e for e in missing if not _is_do_not_translate(e)]
+        print(
+            f"Skipping {len(skipped_dnt)} do-not-translate entries (literal "
+            f"tokens / translator-marked); they are left untranslated.",
+            file=sys.stderr,
+        )
+
     if min_context > 0:
         before = len(missing)
         missing = [
diff --git a/tests/unit_tests/scripts/translations/backfill_po_test.py b/tests/unit_tests/scripts/translations/backfill_po_test.py
index 6734362b0ae..f9b81e9f3cf 100644
--- a/tests/unit_tests/scripts/translations/backfill_po_test.py
+++ b/tests/unit_tests/scripts/translations/backfill_po_test.py
@@ -436,3 +436,29 @@ def test_resilient_translate_propagates_runtime_error(
     monkeypatch.setattr(backfill_po, "translate_batch", _boom)
     with pytest.raises(RuntimeError):
         backfill_po._resilient_translate("m", "fr", [_qitem("Alpha")], {})
+
+
+# --- _is_do_not_translate: never machine-fill literal tokens -------------------
+
+
+def test_is_do_not_translate_curated_msgid() -> None:
+    """A msgid in the curated DO_NOT_TRANSLATE set is protected (icon names,
+    enum values, SQL keywords, API field names, placeholders)."""
+    for msgid in ("bolt", "error_message", "step-after", "GROUP BY"):
+        assert backfill_po._is_do_not_translate(polib.POEntry(msgid=msgid, msgstr=""))
+
+
+def test_is_do_not_translate_honors_translator_comment() -> None:
+    """An explicit do-not-translate translator comment is honored, in any
+    language (e.g. the ru catalog's Cyrillic marker) and phrasing."""
+    for comment in ("Не переводить", "do not translate", "DO-NOT-TRANSLATE"):
+        entry = polib.POEntry(msgid="Some label", msgstr="")
+        entry.tcomment = comment
+        assert backfill_po._is_do_not_translate(entry)
+
+
+def test_is_do_not_translate_allows_normal_entry() -> None:
+    """An ordinary translatable string is not flagged."""
+    entry = polib.POEntry(msgid="Save dashboard", msgstr="")
+    entry.tcomment = "Machine-translated via backfill_po.py (claude-x) [no refs]"
+    assert not backfill_po._is_do_not_translate(entry)