not really. sda3 is a physical volume (PV) which hosts a Logical Volume (LV) with a file system. maybe do some reading about LVM.
- LVM - ArchWiki !!!
- Add storage to your Fedora system with LVM - Fedora Magazine
- A Linux user's guide to Logical Volume Management | Opensource.com
- Lvm - Ubuntu Wiki
- 3.3. LVM Logical Volumes Red Hat Enterprise Linux 6 | Red Hat Customer Portal
Similar topic: How to add unallocated disk space to LVM /home