diff --git a/internal/debug.cc b/internal/debug.cc
index b36e5a8..1a56981 100644
--- a/internal/debug.cc
+++ b/internal/debug.cc
@@ -319,9 +319,11 @@ void CLD2_Debug(const char* text,
     // Score boosts for langprior and distinct tokens
     // Get boosts for current script
     const LangBoosts* langprior_boost = &scoringcontext->langprior_boost.latn;
+    const LangBoosts* langprior_whack = &scoringcontext->langprior_whack.latn;
     const LangBoosts* distinct_boost = &scoringcontext->distinct_boost.latn;
     if (scoringcontext->ulscript != ULScript_Latin) {
       langprior_boost = &scoringcontext->langprior_boost.othr;
+      langprior_whack = &scoringcontext->langprior_whack.othr;
       distinct_boost = &scoringcontext->distinct_boost.othr;
     }
     fprintf(df, "LangPrior_boost: ");
@@ -332,6 +334,14 @@ void CLD2_Debug(const char* text,
                 GetLangProbTxt(scoringcontext, langprob).c_str());
       }
     }
+    fprintf(df, "LangPrior_whack: ");
+    for (int k = 0; k < kMaxBoosts; ++k) {
+      uint32 langprob = langprior_whack->langprob[k];
+      if (langprob > 0) {
+        fprintf(df, "%s&nbsp;&nbsp; ",
+                GetLangProbTxt(scoringcontext, langprob).c_str());
+      }
+    }
     fprintf(df, "Distinct_boost: ");
     for (int k = 0; k < kMaxBoosts; ++k) {
       uint32 langprob = distinct_boost->langprob[k];
diff --git a/internal/scoreonescriptspan.cc b/internal/scoreonescriptspan.cc
index 0d30059..a581885 100644
--- a/internal/scoreonescriptspan.cc
+++ b/internal/scoreonescriptspan.cc
@@ -34,6 +34,11 @@ void AddLangProb(uint32 langprob, Tote* chunk_tote) {
   ProcessProbV2Tote(langprob, chunk_tote);
 }
 
+void ZeroPSLang(uint32 langprob, Tote* chunk_tote) {
+  uint8 top1 = (langprob >> 8) & 0xff;
+  chunk_tote->SetScore(top1, 0);
+}
+
 bool SameCloseSet(uint16 lang1, uint16 lang2) {
   int lang1_close_set = LanguageCloseSet(static_cast<Language>(lang1));
   if (lang1_close_set == 0) {return false;}
@@ -118,9 +123,11 @@ void AddDistinctBoost2(uint32 langprob, ScoringContext* scoringcontext) {
 void ScoreBoosts(const ScoringContext* scoringcontext, Tote* chunk_tote) {
   // Get boosts for current script
   const LangBoosts* langprior_boost = &scoringcontext->langprior_boost.latn;
+  const LangBoosts* langprior_whack = &scoringcontext->langprior_whack.latn;
   const LangBoosts* distinct_boost = &scoringcontext->distinct_boost.latn;
   if (scoringcontext->ulscript != ULScript_Latin) {
     langprior_boost = &scoringcontext->langprior_boost.othr;
+    langprior_whack = &scoringcontext->langprior_whack.othr;
     distinct_boost = &scoringcontext->distinct_boost.othr;
   }
 
@@ -132,6 +139,14 @@ void ScoreBoosts(const ScoringContext* scoringcontext, Tote* chunk_tote) {
     uint32 langprob = distinct_boost->langprob[k];
     if (langprob > 0) {AddLangProb(langprob, chunk_tote);}
   }
+  // boost has a packed set of per-script langs and probabilites
+  // whack has a packed set of per-script lang to be suppressed (zeroed)
+  // When a language in a close set is given as an explicit hint, others in
+  //  that set will be whacked here.
+  for (int k = 0; k < kMaxBoosts; ++k) {
+    uint32 langprob = langprior_whack->langprob[k];
+    if (langprob > 0) {ZeroPSLang(langprob, chunk_tote);}
+  }
 }
 
 
diff --git a/internal/scoreonescriptspan.h b/internal/scoreonescriptspan.h
index a6c2768..b6f9b52 100644
--- a/internal/scoreonescriptspan.h
+++ b/internal/scoreonescriptspan.h
@@ -136,7 +136,12 @@ typedef struct {
   bool flags_cld2_verbose;
   ULScript ulscript;        // langprobs below are with respect to this script
   Language prior_chunk_lang;          // Mostly for debug output
+  // boost has a packed set of per-script langs and probabilites
+  // whack has a per-script lang to be suppressed from ever scoring (zeroed)
+  // When a language in a close set is given as an explicit hint, others in
+  //  that set will be whacked.
   PerScriptLangBoosts langprior_boost;  // From http content-lang or meta lang=
+  PerScriptLangBoosts langprior_whack;  // From http content-lang or meta lang=
   PerScriptLangBoosts distinct_boost;   // From distinctive letter groups
   int oldest_distinct_boost;          // Subscript in hitbuffer of oldest
                                       // distinct score to use
@@ -146,6 +151,7 @@ typedef struct {
   // Inits boosts
   void init() {
     memset(&langprior_boost, 0, sizeof(langprior_boost));
+    memset(&langprior_whack, 0, sizeof(langprior_whack));
     memset(&distinct_boost, 0, sizeof(distinct_boost));
   };
 } ScoringContext;