在许多编程语言中，可以使用正则表达式来实现不区分大小写的单词边界。下面是一些常用编程语言的示例代码：

1. JavaScript:

const regex = /\bword\b/i;
const text = "This is a Word example.";
console.log(regex.test(text)); // Output: true

2. Python:

import re
pattern = r"\bword\b"
text = "This is a Word example."
print(re.search(pattern, text, re.IGNORECASE))  # Output: 

3. Java:

import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class Main {
    public static void main(String[] args) {
        String regex = "\\bword\\b";
        String text = "This is a Word example.";
        Pattern pattern = Pattern.compile(regex, Pattern.CASE_INSENSITIVE);
        Matcher matcher = pattern.matcher(text);
        if (matcher.find()) {
            System.out.println("Match found!");
        } else {
            System.out.println("Match not found!");
        }
    }
}

4. C#:

using System;
using System.Text.RegularExpressions;

class Program
{
    static void Main()
    {
        string pattern = @"\bword\b";
        string text = "This is a Word example.";
        bool isMatch = Regex.IsMatch(text, pattern, RegexOptions.IgnoreCase);
        Console.WriteLine(isMatch); // Output: True
    }
}

这些示例代码使用正则表达式中的\b来表示单词边界，并使用相应编程语言的选项（如i或IGNORECASE）来忽略大小写。