For the slang meaning of terms, you might check the Urban Dictionary, available for iPhone or PC. “Mowing the Lawn” is a slang term for shaving the hair from your pubic region.

When grass is growing fastest in mid-spring, this may mean mowing twice a week or every four or five days. It's much better to cut that often than to wait a few more days and end up having to whack 3 inches off of a 6-inch stand. That's not only a shock to the grass but creates an unusually large mass of clippings.

Mowing is stressful on your grass. Because of this, you don't want to cut when it's already under incredible environmental stress, like a lengthy dry spell or severe drought. When drought-stressed, it's hard enough on your grass; don't compound it and mow during this time.

Some grasses spread quickly by sending out runners. Other types of grass don't spread as fast. Either way, cutting grass encourages it to put it's energy into roots and new shoots instead of height. This will help your grass to both spread and thicken.