C

cell
The intersection of a row and a column
cell reference
The columns letter followed by the row numbers, like A1 or BC575.
cell style
A combination of choices of formats that is named and can be used again for other cells.
chart area
The area that contain all of the parts of the chart, including the titles and legend.
chart tips
Popup tips that tell what each part of a chart is or its values.
chart title
The title assigned to the chart, usually at the top.
chart type
Type of chart, like column, pie, area, donut, etc.
Column chart
Chart Wizard
A set of dialogs which guide you through the process of creating a chart based on your data .
circular reference
A formula that uses the cell reference of the cell that the formula itself is in.
Clear
A command that opens a menu of choices or what you want cleared: All, Formats, Contents, Comments.
clear data
Erase data from a cell. Formatting is still assigned to the cell and will be used for any new data. Clearing the data does not delete the cell itself, just the contents.
clear formats
Returns the selected cells to the default formatting.
Collapse Dialog button
 A button which collapses the dialog to show just a text box for cell references. Clicking or dragging in the spreadsheet puts those cell references in the text box.
collapse group
In a subtotals sheet, clicking the Collapse button will remove from view the rows in that level of the sheet
column
A vertical set of cells, running from the top of the sheet all the way to the bottom of the sheet
column chart
A chart which displays the data as a set of columns.Column chart
 
column heading
A button which shows the letter name of the column
column label
A title that you enter in a cell for a column of cells  
column width
The horizontal size of a columns of cells.
Comma
A button on the toolbar which will apply the comma number format to selected cells. In this format, groups of 3 digits to the left of the decimal point are separated by commas and 2 digits are shown to the right of the decimal point.
comment
An note attached to a cell. The default is a pale yellow rectangle. A comment can be hidden. The shape can be changed to any AutoShape. Text in a comment can be formatted. Comments often explain something about the source or formatting or use of the cell contents.
comment indicator
A small red triangle in the upper right corner of a cell indicates that there is a comment attached to the cell.
concatenation
Combining text and values into one text string.  If the formula in cell D10 is   ="Final Total is " + C4 + " ."  and the value of cell C4 is 560, then what you see in cell D10 is  The Final Total is 560. 
conditional formatting
Formatting that changes based on a logical test. Fonts, borders, and patterns can all be changed. Up to three different conditions can be set for a cell.
convert
To change the type of object or file. You might convert a Lotus 1-2-3 worksheet to a Microsoft Excel worksheet or to a picture.
Currency
A button on the toolbar which applies the Currency number format to the selected cells. In this format numbers have a symbol for the particular currency chosen, such as $ or €. Two digits are shown to the right of the decimal point.
custom list
A sorting list that you create yourself.
customize toolbar
Add or remove items from a toolbar.