A middle section, especially the midriff of the human body.(noun)
American Heritage(R) Dictionary of the English Language, Fifth Edition. Copyright (c) 2011 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Use "midsection" in a sentence
"The dullish midsection is redeemed by the latter part of the book, though."
"PS I went to the gym last night for the first time since September and my midsection is on fire."
"Research has indicated that people with too much fat in their midsection are at greater risk of developing dementia, including Alzheimer's disease."