Combine adjacent cells into a single cell or split a cell in two.
Welcome to ‘Merge Cells’ where you can combine adjacent cells into a single cell. It’s very handy for table formatting tricks and other unusual situations like a longer than common text label.
Or a three row heading like this with various merged cells to create covering headings like ‘Crew’ and ‘Lunar Landing’ :
To merge cells, select them then click Table Tools | Layout | Merge Cells.
Cells to merge have to be entirely, not partially adjacent to each other. The Merge Cells button will be unavailable/greyed out if the selected cells can’t be merged.
As you can see, on the ribbon there is also a ‘Split Cells’ option which can reverse an earlier Merge Cell or be used for a different type of special case.