Tasteless and other bugs
Perl, 47 43 41 + 1 = 42 bytes
-4 bytes thanks to @Sunny Pun.  -2 bytes thanks to @Brad Gilbert b2gills and @Downgoat
Run with the -n flag.
say!/^(s(in?)?|co?|t(an?)?|ln?|log?|e)+$/

It can definitely be golfed futher, but in the spirit of competition, I'm leaving the mostly-original regex I came up with at the beginning.
Returns nothing if true, 1 if false.
Try it online!
I downloaded a dictionary file, and the longest word I found was 11 letters -- tattletales