conditional formatting if any of multiple text in cell itself

For multiple cells in a fairly large spreadsheet, I would like to use conditional formatting (e.g. apply a red highlighted background) if the cell itself is equal to any of about 20 potential words (examples of these words are "unknown" or "N/A" or "not computed" or "score not calculated" or "Not reported", etc.). I would want the conditional statement to say something like, "If cell is equal to = "unknown" or "N/A" or "not computed" or "not reported" then turn cell red.

This is a data entry page that my data entry staff will be entering data into based on preset dropdown lists that I've already set. I just want to the file to automatically highlight in red the cells in which my data entry staff entered the specific words listed above, so that I can quickly scan the document and discuss the "red" cells with my data entry staff.

Thanks for your help! This is very close to solving my problem.

To continue your example. If I named a list of 20 words "words" then I want cell C45 to turn red if the value in C45 is somewhere in "words" list then I would give C45 the conditional format of =MATCH(C45,words,0) and then it works perfectly for C45.

But I would like to apply this formula to about 120 other noncontiguous cells across multiple sheets (e.g. LL3, RQ24, B34, A2, F34, D200, etc....on to naming about 120 other random cells). So that, for example, LL3 turns red if =MATCH(LL3,words,0), etc.

How could I apply this formula to all these extra cells all one time by CTRL+selecting all 120 cells and then writing in the formula one time. Instead of having to individually write a separate code 120 times for 120 cells.