const regex = /(?:\d+[a-z]|[a-z]+\d)[a-z\d]*/gm;
// Alternative syntax using RegExp constructor
// const regex = new RegExp('(?:\\d+[a-z]|[a-z]+\\d)[a-z\\d]*', 'gm')
const str = `asdasdas7
7sdfdf
a1
1a
0001a
0000a0000
a-1
1-a
a
1
eee
21123124
aaaa-111
1 a 6858 ghg 8768-zzt zz zt t-3
1212231234_sdfs1111dfsdf_ewrwerfwe_sef3325345`;
const subst = ``;
// The substituted value will be contained in the result variable
const result = str.replace(regex, subst);
console.log('Substitution result: ', result);
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for JavaScript, please visit: https://developer.mozilla.org/en/docs/Web/JavaScript/Guide/Regular_Expressions