diff --git a/scintilla/src/Document.cxx b/scintilla/src/Document.cxx
index a3fe39557d..bd235abbd4 100644
--- a/scintilla/src/Document.cxx
+++ b/scintilla/src/Document.cxx
@@ -2651,10 +2651,30 @@ class DocumentIndexer : public CharacterIndexer {
 
 	char CharAt(Sci::Position index) const noexcept override {
 		if (index < 0 || index >= end)
-			return 0;
+			return '\0';
 		else
 			return pdoc->CharAt(index);
 	}
+
+	bool IsWordStartAt(Sci::Position pos) const noexcept override {
+		return pdoc->IsWordStartAt(pos);
+	}
+
+	bool IsWordEndAt(Sci::Position pos) const noexcept override {
+		return pdoc->IsWordEndAt(pos);
+	}
+
+	Sci::Position MovePositionOutsideChar(Sci::Position pos, Sci::Position moveDir) const noexcept override {
+		return pdoc->MovePositionOutsideChar(pos, moveDir, true);
+	}
+
+	Sci::Position NextPosition(Sci::Position pos, int moveDir) const noexcept override {
+		return pdoc->NextPosition(pos, moveDir);
+	}
+
+	Sci::Position ExtendWordSelect(Sci::Position pos, int delta) const noexcept override {
+		return pdoc->ExtendWordSelect(pos, delta, true);
+	}
 };
 
 #ifndef NO_CXX11_REGEX
diff --git a/scintilla/src/RESearch.cxx b/scintilla/src/RESearch.cxx
index a65c8992df..22c32db856 100644
--- a/scintilla/src/RESearch.cxx
+++ b/scintilla/src/RESearch.cxx
@@ -233,6 +233,12 @@ using namespace Scintilla;
 #define CLQ     12 /* 0 to 1 closure */
 #define LCLO    13 /* lazy closure */
 
+// experimental
+#define EXP_MATCH_WORD_START	14
+#define EXP_MATCH_WORD_END		15
+#define EXP_MATCH_TO_WORD_END		16
+#define EXP_MATCH_TO_WORD_END_OPT	17
+
 #define END     0
 
 /*
@@ -642,6 +648,11 @@ const char *RESearch::DoCompile(const char *pattern, Sci::Position length, bool
 				break;
 			}
 
+			if (*p == '?' && *lp == EXP_MATCH_TO_WORD_END) {
+				*lp = EXP_MATCH_TO_WORD_END_OPT;
+				break;
+			}
+
 			if (*p == '+') {
 				for (sp = mp; lp < sp; lp++) {
 					*mp++ = *lp;
@@ -672,6 +683,17 @@ const char *RESearch::DoCompile(const char *pattern, Sci::Position length, bool
 					return badpat("Null pattern inside \\<\\>");
 				*mp++ = EOW;
 				break;
+			case 'h':
+				*mp++ = EXP_MATCH_WORD_START;
+				break;
+			case 'H':
+				if (*sp == EXP_MATCH_WORD_START)
+					return badpat("Null pattern inside \\h\\H");
+				*mp++ = EXP_MATCH_WORD_END;
+				break;
+			case 'i':
+				*mp++ = EXP_MATCH_TO_WORD_END;
+				break;
 			case '1':
 			case '2':
 			case '3':
@@ -828,10 +850,11 @@ int RESearch::Execute(const CharacterIndexer &ci, Sci::Position lp, Sci::Positio
 		// fall through
 	default:			/* regular matching all the way. */
 		while (lp < endp) {
-			ep = PMatch(ci, lp, endp, ap);
+			Sci::Position offset = 1;
+			ep = PMatch(ci, lp, endp, ap, 1, &offset);
 			if (ep != NOTFOUND)
 				break;
-			lp++;
+			lp += offset;
 		}
 		break;
 	case END:			/* munged automaton. fail always */
@@ -888,7 +911,7 @@ static inline int isinset(const char *ap, unsigned char c) noexcept {
 #define CHRSKIP 3	/* [CLO] CHR chr END      */
 #define CCLSKIP 34	/* [CLO] CCL 32 bytes END */
 
-Sci::Position RESearch::PMatch(const CharacterIndexer &ci, Sci::Position lp, Sci::Position endp, char *ap) {
+Sci::Position RESearch::PMatch(const CharacterIndexer &ci, Sci::Position lp, Sci::Position endp, char *ap, int moveDir, Sci::Position *offset) {
 	int op;
 	int c;
 	int n;
@@ -938,6 +961,36 @@ Sci::Position RESearch::PMatch(const CharacterIndexer &ci, Sci::Position lp, Sci
 			if (lp == bol || !iswordc(ci.CharAt(lp - 1)) || iswordc(ci.CharAt(lp)))
 				return NOTFOUND;
 			break;
+		case EXP_MATCH_WORD_START:
+			if (!ci.IsWordStartAt(lp)) {
+				if (offset) {
+					e = ci.MovePositionOutsideChar(lp, moveDir);
+					*offset = (e == lp) ? ci.NextPosition(lp, moveDir) - lp : e - lp;
+				}
+				return NOTFOUND;
+			}
+			break;
+		case EXP_MATCH_WORD_END:
+			if (lp == bol || !ci.IsWordEndAt(lp)) {
+				if (offset) {
+					e = ci.MovePositionOutsideChar(lp, moveDir);
+					*offset = (e == lp) ? ci.NextPosition(lp, moveDir) - lp : e - lp;
+				}
+				return NOTFOUND;
+			}
+			break;
+		case EXP_MATCH_TO_WORD_END:
+		case EXP_MATCH_TO_WORD_END_OPT: {
+			e = ci.ExtendWordSelect(lp, moveDir);
+			const bool find = ci.IsWordEndAt(e);
+			if (offset) {
+				*offset = (e == lp) ? ci.NextPosition(lp, moveDir) - lp : e - lp;
+			}
+			if ((e == lp && op != EXP_MATCH_TO_WORD_END_OPT) || !find) {
+				return NOTFOUND;
+			}
+			lp = e;
+		} break;
 		case REF:
 			n = *ap++;
 			bp = bopat[n];
@@ -992,13 +1045,14 @@ Sci::Position RESearch::PMatch(const CharacterIndexer &ci, Sci::Position lp, Sci
 			e = NOTFOUND;
 			while (llp >= are) {
 				Sci::Position q;
-				if ((q = PMatch(ci, llp, endp, ap)) != NOTFOUND) {
+				Sci::Position qoff = -1;
+				if ((q = PMatch(ci, llp, endp, ap, -1, &qoff)) != NOTFOUND) {
 					e = q;
 					lp = llp;
 					if (op != LCLO) return e;
 				}
 				if (*ap == END) return e;
-				--llp;
+				llp += qoff;
 			}
 			if (*ap == EOT)
 				PMatch(ci, lp, endp, ap);
diff --git a/scintilla/src/RESearch.h b/scintilla/src/RESearch.h
index beb8e395fd..f32a05772c 100644
--- a/scintilla/src/RESearch.h
+++ b/scintilla/src/RESearch.h
@@ -22,6 +22,11 @@ namespace Scintilla {
 class CharacterIndexer {
 public:
 	virtual char CharAt(Sci::Position index) const noexcept = 0;
+	virtual bool IsWordStartAt(Sci::Position pos) const noexcept = 0;
+	virtual bool IsWordEndAt(Sci::Position pos) const noexcept = 0;
+	virtual Sci::Position MovePositionOutsideChar(Sci::Position pos, Sci::Position moveDir) const noexcept = 0;
+	virtual Sci::Position NextPosition(Sci::Position pos, int moveDir) const noexcept = 0;
+	virtual Sci::Position ExtendWordSelect(Sci::Position pos, int delta) const noexcept = 0;
 	virtual ~CharacterIndexer() = default;
 };
 
@@ -57,7 +62,7 @@ class RESearch {
 	int GetBackslashExpression(const char *pattern, int &incr) noexcept;
 
 	const char *DoCompile(const char *pattern, Sci::Position length, bool caseSensitive, bool posix) noexcept;
-	Sci::Position PMatch(const CharacterIndexer &ci, Sci::Position lp, Sci::Position endp, char *ap);
+	Sci::Position PMatch(const CharacterIndexer &ci, Sci::Position lp, Sci::Position endp, char *ap, int moveDir = 1, Sci::Position *offset = nullptr);
 
 	Sci::Position bol;
 	Sci::Position tagstk[MAXTAG];  /* subpat tag stack */
diff --git a/src/Notepad2.rc b/src/Notepad2.rc
index db9e9ca61d..069fba457c 100644
--- a/src/Notepad2.rc
+++ b/src/Notepad2.rc
@@ -1738,7 +1738,7 @@ END
 STRINGTABLE
 BEGIN
     IDS_BACKSLASHHELP       "Backslash Transformations\n\n\\a\tAlert (BEL, ASCII 7)\n\\b\tBackspace (BS, ASCII 8)\n\\e\tEscape (ESC, ASCII 27 / 1B)\n\\f\tFormfeed (FF, ASCII 12 / 0C)\n\\n\tNewline (LF, ASCII 10 / 0A)\n\\r\tCarriage return (CR, ASCII 13 / 0D)\n\\t\tHorizontal Tab (HT, ASCII 9)\n\\v\tVertical Tab (VT, ASCII 11 / 0B)\n\\ooo\tOctal Value\n\\u####\tHexadecimal Value\n\\xhh\tHexadecimal Value\n\\\\\tBackslash"
-    IDS_REGEXPHELP          "RegExp Syntax (Single Lines Only)\n\n.\tAny character\n^\tStart of a line\n$\tEnd of a line\n\\<\tStart of a word\n\\>\tEnd of a word\n[...]\tA set of chars ([abc]) or a range ([a-z])\n[^...]\tChars NOT in the set or range\n\\d\tAny decimal digit\n\\D\tAny non-digit char\n\\s\tAny whitespace char\n\\S\tNot a whitespace char\n\\w\tAny ""word"" char\n\\W\tAny ""non-word"" char\n\\x\tEscape character with otherwise special meaning\n\\xHH\tChar with hex code HH\n?\tMatches preceding 0 or 1 times\n*\tMatches preceding 0 or more times\n+\tMatches preceding 1 or more times\n*? or +?\tNon greedy matching of quantifiers ""?"" and ""+""\n(\tStart of a region\n)\tEnd of a region\n\\n\tRefers to a region when replacing (n is 1-9)\n"
+    IDS_REGEXPHELP          "RegExp Syntax (Single Lines Only)\n\n.\tAny character\n^\tStart of a line\n$\tEnd of a line\n\\<\tStart of a word\n\\>\tEnd of a word\n[...]\tA set of chars ([abc]) or a range ([a-z])\n[^...]\tChars NOT in the set or range\n\\d\tAny decimal digit\n\\D\tAny non-digit char\n\\s\tAny whitespace char\n\\S\tAny non-whitespace char\n\\w\tAny ""word"" char\n\\W\tAny ""non-word"" char\n\\x\tEscape character with otherwise special meaning\n\\xHH\tChar with hex code HH\n?\tMatches preceding 0 or 1 times\n*\tMatches preceding 0 or more times\n+\tMatches preceding 1 or more times\n*? or +?\tNon greedy matching of quantifiers ""?"" and ""+""\n(\tStart of a region\n)\tEnd of a region\n\\n\tRefers to a region when replacing (n is 1-9)\n\nExperimental Syntax:\n\h\tStart of a word, according to IsWordStartAt()\n\H\tEnd of a word, according to IsWordEndAt()\n\i\tMatches 1 or more characters to end of a word\n\i?\tMatches 0 or more characters to end of a word"
     IDS_WILDCARDHELP        "Wildcard Search\n\n*\tMatches zero or more characters.\n?\tMatches exactly one character. "
 END