I've never come across the word "lakh" before. I thought it might be the name of a racial grouping. Wikipedia had the answer.Japan needs as much as 3.8 lakh immigrants every year to prevent a decline in the working-age population. It will have to depend upon the workers from countries like India, Bangladesh, Indonesia, Pakistan, Sri Lanka, Thailand and Vietnam to maintain the working-age population at the current level...more...
A lakh (also spelled lac) is a unit in a traditional number system, still widely used in India, equal to a hundred thousand. A hundred lakh makes a crore. This system of measurement also introduces separators into numbers in a different place than is common outside India. For example, 3 million (30 lakh) would be written as 30,00,000.