diff --git a/CHANGELOG.md b/CHANGELOG.md
index 6962dcbd..94166f39 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -2,6 +2,10 @@ To install or update LODA, please follow the [installation instructions](https:/
 
 ## [Unreleased]
 
+### Enhancements
+
+* Rename digit operations
+
 ## v25.1.3
 
 ### Bugfixes
diff --git a/src/eval/interpreter.cpp b/src/eval/interpreter.cpp
index fa28ab7f..046f5183 100644
--- a/src/eval/interpreter.cpp
+++ b/src/eval/interpreter.cpp
@@ -80,11 +80,11 @@ Number Interpreter::calc(const Operation::Type type, const Number& target,
     case Operation::Type::NRT: {
       return Semantics::nrt(target, source);
     }
-    case Operation::Type::DIS: {
-      return Semantics::dis(target, source);
+    case Operation::Type::DGS: {
+      return Semantics::dgs(target, source);
     }
-    case Operation::Type::DIR: {
-      return Semantics::dir(target, source);
+    case Operation::Type::DGR: {
+      return Semantics::dgr(target, source);
     }
     case Operation::Type::EQU: {
       return Semantics::equ(target, source);
diff --git a/src/eval/semantics.cpp b/src/eval/semantics.cpp
index aca40458..145158d9 100644
--- a/src/eval/semantics.cpp
+++ b/src/eval/semantics.cpp
@@ -223,7 +223,7 @@ Number Semantics::nrt(const Number& a, const Number& b) {
   return r;
 }
 
-Number Semantics::dis(const Number& a, const Number& b) {
+Number Semantics::dgs(const Number& a, const Number& b) {
   if (a == Number::INF || b == Number::INF || b < Number::TWO) {
     return Number::INF;
   }
@@ -237,7 +237,7 @@ Number Semantics::dis(const Number& a, const Number& b) {
   return mul(sign, r);
 }
 
-Number Semantics::dir(const Number& a, const Number& b) {
+Number Semantics::dgr(const Number& a, const Number& b) {
   if (a == Number::INF || b == Number::INF || b < Number::TWO) {
     return Number::INF;
   }
diff --git a/src/eval/semantics.hpp b/src/eval/semantics.hpp
index 941bd606..40f57989 100644
--- a/src/eval/semantics.hpp
+++ b/src/eval/semantics.hpp
@@ -30,9 +30,9 @@ class Semantics {
 
   static Number nrt(const Number& a, const Number& b);
 
-  static Number dis(const Number& a, const Number& b);
+  static Number dgs(const Number& a, const Number& b);
 
-  static Number dir(const Number& a, const Number& b);
+  static Number dgr(const Number& a, const Number& b);
 
   static Number equ(const Number& a, const Number& b);
 
diff --git a/src/lang/program.cpp b/src/lang/program.cpp
index 026fb2f8..7548a0f2 100644
--- a/src/lang/program.cpp
+++ b/src/lang/program.cpp
@@ -8,7 +8,7 @@ const std::array<Operation::Type, 33> Operation::Types = {
     Operation::Type::DIV, Operation::Type::DIF, Operation::Type::MOD,
     Operation::Type::POW, Operation::Type::GCD, Operation::Type::LEX,
     Operation::Type::BIN, Operation::Type::LOG, Operation::Type::NRT,
-    Operation::Type::DIS, Operation::Type::DIR, Operation::Type::EQU,
+    Operation::Type::DGS, Operation::Type::DGR, Operation::Type::EQU,
     Operation::Type::NEQ, Operation::Type::LEQ, Operation::Type::GEQ,
     Operation::Type::MIN, Operation::Type::MAX, Operation::Type::BAN,
     Operation::Type::BOR, Operation::Type::BXO, Operation::Type::LPB,
@@ -47,10 +47,10 @@ const Operation::Metadata& Operation::Metadata::get(Type t) {
       Operation::Type::LOG, "log", 2, true, true, true};
   static Operation::Metadata nrt{
       Operation::Type::NRT, "nrt", 2, true, true, true};
-  static Operation::Metadata dis{
-      Operation::Type::DIS, "dis", 2, true, true, true};
-  static Operation::Metadata dir{
-      Operation::Type::DIR, "dir", 2, true, true, true};
+  static Operation::Metadata dgs{
+      Operation::Type::DGS, "dgs", 2, true, true, true};
+  static Operation::Metadata dgr{
+      Operation::Type::DGR, "dgr", 2, true, true, true};
   static Operation::Metadata equ{
       Operation::Type::EQU, "equ", 2, true, true, true};
   static Operation::Metadata neq{
@@ -114,10 +114,10 @@ const Operation::Metadata& Operation::Metadata::get(Type t) {
       return log;
     case Operation::Type::NRT:
       return nrt;
-    case Operation::Type::DIS:
-      return dis;
-    case Operation::Type::DIR:
-      return dir;
+    case Operation::Type::DGS:
+      return dgs;
+    case Operation::Type::DGR:
+      return dgr;
     case Operation::Type::EQU:
       return equ;
     case Operation::Type::NEQ:
@@ -163,9 +163,16 @@ const Operation::Metadata& Operation::Metadata::get(const std::string& name) {
       return m;
     }
   }
-  if (name == "cmp") {  // backwards compatibility
+  // for backwards compatibility
+  if (name == "cmp") {
     return get(Operation::Type::EQU);
   }
+  if (name == "dis") {
+    return get(Operation::Type::DGS);
+  }
+  if (name == "dir") {
+    return get(Operation::Type::DGR);
+  }
   throw std::runtime_error("invalid operation: " + name);
 }
 
diff --git a/src/lang/program.hpp b/src/lang/program.hpp
index 674b67e3..b06701a8 100644
--- a/src/lang/program.hpp
+++ b/src/lang/program.hpp
@@ -49,8 +49,8 @@ class Operation {
     BIN,     // binomial coefficient
     LOG,     // logarithm
     NRT,     // n-th root
-    DIS,     // digit sum
-    DIR,     // digital root
+    DGS,     // digit sum
+    DGR,     // digital root
     EQU,     // equality
     NEQ,     // inequality
     LEQ,     // less or equal
diff --git a/src/mine/iterator.cpp b/src/mine/iterator.cpp
index e3875c62..2ec5a900 100644
--- a/src/mine/iterator.cpp
+++ b/src/mine/iterator.cpp
@@ -101,14 +101,14 @@ bool Iterator::inc(Operation& op) {
       return true;
 
     case Operation::Type::BIN:
-      op.type = Operation::Type::DIS;
+      op.type = Operation::Type::DGS;
       return true;
 
-    case Operation::Type::DIS:
-      op.type = Operation::Type::DIR;
+    case Operation::Type::DGS:
+      op.type = Operation::Type::DGR;
       return true;
 
-    case Operation::Type::DIR:
+    case Operation::Type::DGR:
       op.type = Operation::Type::EQU;
       return true;
 
diff --git a/tests/semantics/dir.csv b/tests/semantics/dgr.csv
similarity index 100%
rename from tests/semantics/dir.csv
rename to tests/semantics/dgr.csv
diff --git a/tests/semantics/dis.csv b/tests/semantics/dgs.csv
similarity index 100%
rename from tests/semantics/dis.csv
rename to tests/semantics/dgs.csv