What does the prefix "kilo-" signify in terms of base units?

The prefix "kilo-" is a metric prefix that specifically indicates a factor of one thousand (1,000) relative to the base unit. This means that when "kilo-" is used, it signifies that the quantity is being multiplied by 1,000. For instance, one kilometer (km) refers to one thousand meters (m), making it clear how the prefix serves to scale the base unit up by a significant factor. This understanding of "kilo-" is fundamental in both scientific measurements and everyday use, as it aids in conveying large quantities in a more manageable form.