entrepreneur.js

var spellings = ['(E|e)nt', ['rep', 'ep'], ['ren', 'en'], ['eur', 'er']];
//var endings = ['', 'ship', 'ial'];

var parts = [];

for (var i = 0; i < spellings.length; i++) {
	if (spellings[i] instanceof Array) {
		parts.push('(?:');
		for (var j = 0; j < spellings[i].length; j++) {
			parts.push(spellings[i][j]);
			parts.push('|');
		}
		parts.pop();
		parts.push(')');
	} else { // String
		parts.push(spellings[i]);
	}
}

var regex = new RegExp(parts.join(''), 'g');