diff --git a/internal/spell/aff.go b/internal/spell/aff.go
index 32b365384..5f72cc22a 100644
--- a/internal/spell/aff.go
+++ b/internal/spell/aff.go
@@ -62,13 +62,39 @@ type dictConfig struct {
 	TryChars          string
 	WordChars         string
 	CompoundOnly      string
-	AffixMap          map[rune]affix
+	AffixMap          map[string]affix
 	CamelCase         int
 	CompoundMin       int64
-	compoundMap       map[rune][]string
+	compoundMap       map[string][]string
 	NoSuggestFlag     string
 }
 
+// parseFlags splits a flag string into individual flags based on the FLAG type.
+//
+// Hunspell supports several flag formats:
+//   - "ASCII" (default): each character is a flag
+//   - "num": flags are comma-separated numbers (e.g., "14308,10482,4720")
+//   - "UTF-8": each UTF-8 character is a flag
+//   - "long": each pair of ASCII characters is a flag
+func (a dictConfig) parseFlags(flagStr string) []string {
+	switch a.Flag {
+	case "num":
+		return strings.Split(flagStr, ",")
+	case "long":
+		flags := make([]string, 0, len(flagStr)/2)
+		for i := 0; i+1 < len(flagStr); i += 2 {
+			flags = append(flags, flagStr[i:i+2])
+		}
+		return flags
+	default: // "ASCII" or "UTF-8"
+		flags := make([]string, 0, len(flagStr))
+		for _, r := range flagStr {
+			flags = append(flags, string(r))
+		}
+		return flags
+	}
+}
+
 // expand expands a word/affix using dictionary/affix rules
 //
 //	This also supports CompoundRule flags
@@ -87,11 +113,13 @@ func (a dictConfig) expand(wordAffix string, out []string) ([]string, error) {
 	// safe
 	word, keyString := wordAffix[:idx], wordAffix[idx+1:]
 
+	flags := a.parseFlags(keyString)
+
 	// check to see if any of the flags are in the
 	// "compound only".  If so then nothing to add
 	compoundOnly := false
-	for _, key := range keyString {
-		if strings.ContainsRune(a.CompoundOnly, key) {
+	for _, key := range flags {
+		if key == a.CompoundOnly {
 			compoundOnly = true
 			continue
 		}
@@ -110,12 +138,9 @@ func (a dictConfig) expand(wordAffix string, out []string) ([]string, error) {
 	out = append(out, word)
 	prefixes := make([]affix, 0, 5)
 	suffixes := make([]affix, 0, 5)
-	for _, key := range keyString {
-		// want keyString to []?something?
-		// then iterate over that
+	for _, key := range flags {
 		af, ok := a.AffixMap[key]
 		if !ok {
-			// TODO: How should we handle this?
 			continue
 		}
 		if !af.CrossProduct {
@@ -161,8 +186,8 @@ func isCrossProduct(val string) (bool, error) {
 func newDictConfig(file io.Reader) (*dictConfig, error) { //nolint:funlen
 	aff := dictConfig{
 		Flag:        "ASCII",
-		AffixMap:    make(map[rune]affix),
-		compoundMap: make(map[rune][]string),
+		AffixMap:    make(map[string]affix),
+		compoundMap: make(map[string][]string),
 		CompoundMin: 3, // default in Hunspell
 	}
 	scanner := bufio.NewScanner(file)
@@ -219,9 +244,9 @@ func newDictConfig(file io.Reader) (*dictConfig, error) { //nolint:funlen
 				aff.CompoundRule = make([]string, 0, val)
 			} else {
 				aff.CompoundRule = append(aff.CompoundRule, parts[1])
-				for _, char := range parts[1] {
-					if _, ok := aff.compoundMap[char]; !ok {
-						aff.compoundMap[char] = []string{}
+				for _, flag := range aff.parseFlags(parts[1]) {
+					if _, ok := aff.compoundMap[flag]; !ok {
+						aff.compoundMap[flag] = []string{}
 					}
 				}
 			}
@@ -248,8 +273,7 @@ func newDictConfig(file io.Reader) (*dictConfig, error) { //nolint:funlen
 
 			sections := len(parts)
 			if sections > 4 {
-				// does this need to be split out into suffix and prefix?
-				flag := rune(parts[1][0])
+				flag := parts[1]
 				a, ok := aff.AffixMap[flag]
 				if !ok {
 					return nil, fmt.Errorf("got rules for flag %q but no definition", flag)
@@ -299,7 +323,7 @@ func newDictConfig(file io.Reader) (*dictConfig, error) { //nolint:funlen
 					Type:         atype,
 					CrossProduct: cross,
 				}
-				flag := rune(parts[1][0])
+				flag := parts[1]
 				aff.AffixMap[flag] = a
 			}
 		default:
diff --git a/internal/spell/aff_test.go b/internal/spell/aff_test.go
new file mode 100644
index 000000000..5bc1cfb66
--- /dev/null
+++ b/internal/spell/aff_test.go
@@ -0,0 +1,194 @@
+package spell
+
+import (
+	"strings"
+	"testing"
+)
+
+func TestParseFlagsASCII(t *testing.T) {
+	dc := dictConfig{Flag: "ASCII"}
+	flags := dc.parseFlags("ABC")
+	if len(flags) != 3 || flags[0] != "A" || flags[1] != "B" || flags[2] != "C" {
+		t.Errorf("ASCII parseFlags(%q) = %v, want [A B C]", "ABC", flags)
+	}
+}
+
+func TestParseFlagsNum(t *testing.T) {
+	dc := dictConfig{Flag: "num"}
+	flags := dc.parseFlags("14308,10482,4720")
+	if len(flags) != 3 || flags[0] != "14308" || flags[1] != "10482" || flags[2] != "4720" {
+		t.Errorf("num parseFlags(%q) = %v, want [14308 10482 4720]", "14308,10482,4720", flags)
+	}
+}
+
+func TestParseFlagsLong(t *testing.T) {
+	dc := dictConfig{Flag: "long"}
+	flags := dc.parseFlags("AABB")
+	if len(flags) != 2 || flags[0] != "AA" || flags[1] != "BB" {
+		t.Errorf("long parseFlags(%q) = %v, want [AA BB]", "AABB", flags)
+	}
+}
+
+func TestParseFlagsUTF8(t *testing.T) {
+	dc := dictConfig{Flag: "UTF-8"}
+	flags := dc.parseFlags("AğB")
+	if len(flags) != 3 || flags[0] != "A" || flags[1] != "ğ" || flags[2] != "B" {
+		t.Errorf("UTF-8 parseFlags(%q) = %v, want [A ğ B]", "AğB", flags)
+	}
+}
+
+func TestFlagNumAffixParsing(t *testing.T) {
+	// Minimal FLAG num AFF file
+	affContent := `SET UTF-8
+FLAG num
+
+SFX 100 N 1
+SFX 100 0 ler .
+
+SFX 200 N 1
+SFX 200 0 in .
+`
+	aff, err := newDictConfig(strings.NewReader(affContent))
+	if err != nil {
+		t.Fatalf("newDictConfig error: %v", err)
+	}
+
+	if aff.Flag != "num" {
+		t.Errorf("Flag = %q, want %q", aff.Flag, "num")
+	}
+
+	// Check that affix 100 exists with "ler" suffix
+	a100, ok := aff.AffixMap["100"]
+	if !ok {
+		t.Fatal("AffixMap missing flag 100")
+	}
+	if len(a100.Rules) != 1 || a100.Rules[0].AffixText != "ler" {
+		t.Errorf("flag 100 rules = %v, want [{ler}]", a100.Rules)
+	}
+
+	// Check that affix 200 exists with "in" suffix
+	a200, ok := aff.AffixMap["200"]
+	if !ok {
+		t.Fatal("AffixMap missing flag 200")
+	}
+	if len(a200.Rules) != 1 || a200.Rules[0].AffixText != "in" {
+		t.Errorf("flag 200 rules = %v, want [{in}]", a200.Rules)
+	}
+}
+
+func TestFlagNumExpand(t *testing.T) {
+	affContent := `SET UTF-8
+FLAG num
+
+SFX 100 N 1
+SFX 100 0 ler .
+
+SFX 200 N 1
+SFX 200 0 in .
+`
+	aff, err := newDictConfig(strings.NewReader(affContent))
+	if err != nil {
+		t.Fatalf("newDictConfig error: %v", err)
+	}
+
+	// "belge/100,200" should expand to: belge, belgeler, belgein
+	words, err := aff.expand("belge/100,200", nil)
+	if err != nil {
+		t.Fatalf("expand error: %v", err)
+	}
+
+	expected := map[string]bool{"belge": true, "belgeler": true, "belgein": true}
+	for _, w := range words {
+		if !expected[w] {
+			t.Errorf("unexpected word %q in expansion", w)
+		}
+		delete(expected, w)
+	}
+	for w := range expected {
+		t.Errorf("missing expected word %q", w)
+	}
+}
+
+func TestFlagNumGoSpellReader(t *testing.T) {
+	affContent := `SET UTF-8
+FLAG num
+
+SFX 100 N 1
+SFX 100 0 ler .
+
+SFX 200 N 1
+SFX 200 0 nin .
+`
+	dicContent := `2
+belge/100,200
+sistem/100,200
+`
+
+	gs, err := newGoSpellReader(
+		strings.NewReader(affContent),
+		strings.NewReader(dicContent),
+	)
+	if err != nil {
+		t.Fatalf("newGoSpellReader error: %v", err)
+	}
+
+	tests := []struct {
+		word string
+		want bool
+	}{
+		{"belge", true},
+		{"belgeler", true},
+		{"belgenin", true},
+		{"sistem", true},
+		{"sistemler", true},
+		{"sistemnin", true},
+		{"bilinmeyen", false},
+	}
+
+	for _, tt := range tests {
+		got := gs.spell(tt.word)
+		if got != tt.want {
+			t.Errorf("spell(%q) = %v, want %v", tt.word, got, tt.want)
+		}
+	}
+}
+
+func TestASCIFlagBackwardCompatibility(t *testing.T) {
+	// Original ASCII flag format must still work
+	affContent := `SET UTF-8
+
+SFX A N 1
+SFX A 0 s .
+
+SFX B N 1
+SFX B 0 ed .
+`
+	dicContent := `1
+test/AB
+`
+
+	gs, err := newGoSpellReader(
+		strings.NewReader(affContent),
+		strings.NewReader(dicContent),
+	)
+	if err != nil {
+		t.Fatalf("newGoSpellReader error: %v", err)
+	}
+
+	tests := []struct {
+		word string
+		want bool
+	}{
+		{"test", true},
+		{"tests", true},
+		{"tested", true},
+		{"testing", false},
+	}
+
+	for _, tt := range tests {
+		got := gs.spell(tt.word)
+		if got != tt.want {
+			t.Errorf("spell(%q) = %v, want %v", tt.word, got, tt.want)
+		}
+	}
+}
diff --git a/internal/spell/gospell.go b/internal/spell/gospell.go
index cdfec6cde..7eb8652f9 100644
--- a/internal/spell/gospell.go
+++ b/internal/spell/gospell.go
@@ -220,14 +220,17 @@ func newGoSpellReader(aff, dic io.Reader) (*goSpell, error) {
 
 	for _, compoundRule := range affix.CompoundRule {
 		pattern := "^"
-		for _, key := range compoundRule {
-			switch key {
-			case '(', ')', '+', '?', '*':
-				pattern += regexp.QuoteMeta(string(key))
-			default:
-				groups := affix.compoundMap[key]
-				pattern = pattern + "(" + strings.Join(groups, "|") + ")"
+		for _, key := range affix.parseFlags(compoundRule) {
+			if len(key) == 1 {
+				r := rune(key[0])
+				switch r {
+				case '(', ')', '+', '?', '*':
+					pattern += regexp.QuoteMeta(key)
+					continue
+				}
 			}
+			groups := affix.compoundMap[key]
+			pattern = pattern + "(" + strings.Join(groups, "|") + ")"
 		}
 		pattern += "$"