diff --git a/data_preprocess/abbreviations/.gitignore b/data_preprocess/abbreviations/.gitignore
new file mode 100644
index 0000000..bee8a64
--- /dev/null
+++ b/data_preprocess/abbreviations/.gitignore
@@ -0,0 +1 @@
+__pycache__
diff --git a/data_preprocess/abbreviations/README.md b/data_preprocess/abbreviations/README.md
new file mode 100644
index 0000000..b4dbe38
--- /dev/null
+++ b/data_preprocess/abbreviations/README.md
@@ -0,0 +1,7 @@
+## Purpose:
+
+Perform substitutions on common terms to standardize abbreviations.
+
+## Instructions:
+
+- `python abbreviations_replacer.py`
\ No newline at end of file
diff --git a/data_preprocess/abbreviations/abbreviations_replacer.py b/data_preprocess/abbreviations/abbreviations_replacer.py
new file mode 100644
index 0000000..2a40b27
--- /dev/null
+++ b/data_preprocess/abbreviations/abbreviations_replacer.py
@@ -0,0 +1,43 @@
+"""
+Author: Daniel Kim
+Modified by: Richard Wong
+"""
+# %%
+import re
+import pandas as pd
+from replacement_dict import replacement_dict
+
+# %%
+def count_abbreviation_occurrences(tag_descriptions, abbreviation):
+    """Count the number of occurrences of the abbreviation in the list of machine descriptions."""
+    pattern = re.compile(abbreviation)
+    count = sum(len(pattern.findall(description)) for description in tag_descriptions)
+    return count
+
+def replace_abbreviations(tag_descriptions, abbreviations):
+    """Replace the abbreviations according to the key-pair value provided."""
+    replaced_descriptions = []
+    for description in tag_descriptions:
+        for abbreviation, replacement in abbreviations.items():
+            description = re.sub(abbreviation, replacement, description)
+
+        replaced_descriptions.append(description)
+    return replaced_descriptions
+
+
+# %%
+file_path = '../../data_import/exports/raw_data.csv'  # Adjust this path to your actual file location
+df = pd.read_csv(file_path)
+
+# %%
+# Replace abbreviations
+print("running substitution")
+tag_descriptions = df['tag_description'].fillna("N/A")
+replaced_descriptions = replace_abbreviations(tag_descriptions, replacement_dict)
+# print("Descriptions after replacement:", replaced_descriptions)
+
+# %%
+df["tag_description"] = replaced_descriptions
+df.to_csv("../exports/preprocessed_data.csv", index=False)
+print("file saved")
+# %%
diff --git a/data_preprocess/abbreviations/replacement_dict.py b/data_preprocess/abbreviations/replacement_dict.py
new file mode 100644
index 0000000..0475910
--- /dev/null
+++ b/data_preprocess/abbreviations/replacement_dict.py
@@ -0,0 +1,113 @@
+"""
+Author: Daniel Kim
+"""
+
+# Abbreviations and their replacements
+replacement_dict = {
+    r'\bLIST\b': 'LIST',
+    r'\bList\b': 'LIST',
+    r'\bEXH\.': 'EXHAUST',
+    r'\bEXH\b': 'EXHAUST',
+    r'\bEXHAUST\.': 'EXHAUST',
+    r'\bExhaust\b': 'EXHAUST',
+    r'\bEXHAUST\b': 'EXHAUST',
+    r'\bTEMP\.': 'TEMPERATURE',
+    r'\bTEMP\b': 'TEMPERATURE',
+    r'\bTEMPERATURE\.': 'TEMPERATURE',
+    r'\bTEMPERATURE\b': 'TEMPERATURE',
+    r'\bW\.': 'WATER',
+    r'\bWATER\b': 'WATER',
+    r'\bCYL\.': 'CYLINDER',
+    r'\bcyl\.': 'CYLINDER',
+    r'\bCYL\b': 'CYLINDER',
+    r'\bcylinder\b': 'CYLINDER',
+    r'\bCYLINDER\b': 'CYLINDER',
+    r'\bCOOL\.': 'COOLING',
+    r'\bcool\.': 'COOLING',
+    r'\bcooling\b': 'COOLING',
+    r'\bCOOLING\b': 'COOLING',
+    r'\bcooler\b': 'COOLER',
+    r'\bCOOLER\b': 'COOLER',
+    r'\bScav\.': 'SCAVENGE',
+    r'\bSCAV\.': 'SCAVENGE',
+    r'\bINL\.': 'INLET',
+    r'\binlet\b': 'INLET',
+    r'\bINLET\b': 'INLET',
+    r'\bOUT\.': 'OUTLET',
+    r'\bOUTL\.': 'OUTLET',
+    r'\boutlet\b': 'OUTLET',
+    r'\bOUTLET\b': 'OUTLET',
+    r'\bPRESS\.': 'PRESSURE',
+    r'\bPress\.': 'PRESSURE',
+    r'\bpressure\b': 'PRESSURE',
+    r'\bPRESSURE\b': 'PRESSURE',
+    r'\bCLR\b': 'CLEAR',
+    r'\bENG\.': 'ENGINE',
+    r'\bENG\b': 'ENGINE',
+    r'\bENGINE\b': 'ENGINE',
+    r'\bEngine speed\b': 'ENGINE SPEED',
+    r'\bEngine running\b': 'ENGINE RUNNING',
+    r'\bEngine RPM pickup\b': 'ENGINE RPM PICKUP',
+    r'\bEngine room\b': 'ENGINE ROOM',
+    r'\bM/E\b': 'MAIN_ENGINE',
+    r'\bME\b': 'MAIN_ENGINE',
+    r'\bMAIN ENGINE\b': 'MAIN_ENGINE',
+    r'\bGen\b': 'GENERATOR_ENGINE',
+    r'\bGE\b': 'GENERATOR_ENGINE',
+    r'\bG/E\b': 'GENERATOR_ENGINE',
+    r'\bDG': 'GENERATOR_ENGINE',
+    r'\bD/G\b': 'GENERATOR_ENGINE',
+    r'\bGEN\.': 'GENERATOR_ENGINE',
+    r'\bGENERATOR ENGINE\B': 'GENERATOR_ENGINE',
+    r'\bGEN\.WIND\.TEMP\b': 'GENERATOR WINDING TEMPERATURE',
+    r'\bENGINE ROOM\b': 'ENGINE ROOM',
+    r'\bE/R\b': 'ENGINE ROOM',
+    r'\bNO1\b': 'NO.1',
+    r'\bNO\.1\b': 'NO.1',
+    r'\bNo\.1\b': 'NO.1',
+    r'\bNO2\b': 'NO.2',
+    r'\bNO\.2\b': 'NO.2',
+    r'\bNo\.2\b': 'NO.2',
+    r'\bNO3\b': 'NO.3',
+    r'\bNO\.3\b': 'NO.3',
+    r'\bNo\.3\b': 'NO.3',
+    r'\bNO4\b': 'NO.4',
+    r'\bNO\.4\b': 'NO.4',
+    r'\bNo\.4\b': 'NO.4',
+    r'\bNO5\b': 'NO.5',
+    r'\bNO\.5\b': 'NO.5',
+    r'\bNo\.5\b': 'NO.5',
+    r'\bFLTR\b': 'FILTER',
+    r'\bLUB\.': 'LUBRICANT',
+    r'\bM\.G\.O\b': 'MGO',
+    r'\bMGO\b': 'MGO',
+    r'\bF\.O\b': 'FUEL OIL',
+    r'\bFO\b': 'FUEL OIL',
+    r'\bL\.T\b': 'LOW TEMPERATURE',
+    r'\bLT\b': 'LOW TEMPERATURE',
+    r'\bH\.T\b': 'HIGH TEMPERATURE',
+    r'\bHT\b': 'HIGH TEMPERATURE',
+    r'\bAUX\.': 'AUXILIARY',
+    r'\bNO\.2A\b': 'NO.2A',
+    r'\bNO\.2B\b': 'NO.2B',
+    r'\bAUX\.BOILER\b': 'AUXILIARY BOILER',
+    r'\bAUX\. BOILER\b': 'AUXILIARY BOILER',
+    r'\bWIND\.': 'WINDING',
+    r'\bWINDING\b': 'WINDING',
+    r'\bC\.S\.W\b': 'CSW',
+    r'\bCSW\b': 'CSW',
+    r'\bVLOT\.': 'VOLTAGE',
+    r'\bVOLTAGE\b': 'VOLTAGE',
+    r'\bVOLT\.': 'VOLTAGE',
+    r'\bFREQ\.': 'FREQUENCY',
+    r'\bFREQUENCY\b': 'FREQUENCY',
+    r'\bCURR\.': 'CURRENT',
+    r'\bCURRENT\b': 'CURRENT',
+    r'\bH\.F\.O\.': 'HFO',
+    r'\bTCA\b': 'TURBOCHARGER',
+    r'\bTCB\b': 'TURBOCHARGER',
+    r'\bT/C\b': 'TURBOCHARGER',
+    r'\bTC\b': 'TURBOCHARGER',
+    r'\bTURBOCHAGER\b': 'TURBOCHARGER',
+    r'\bTURBOCHARGER\b': 'TURBOCHARGER'
+}
\ No newline at end of file