Tasteless and other bugs Some versions of the standard Android calculator app allow you to press a key, like 'sin' and then the 'del' key to make it 'si'. Probably just a bug which they can't be bothered with removing.



The following letters/letter groupings are typable:

 

sin
si
s
cos
co
c
tan
ta
t
ln
l
log
lo
e



So, 'tasteless' is typable, because ta-s-t-e-l-e-s-s and so is 'clogs' because 'c-log-s'. However 'got' is not typable, neither is 'an' or 'xyz'.

Write a program that takes a single word (or sequence of letters, only a-z in input) as input and produces output to indicate if a word is typable or not.

Output may be a single character/letter/digit/etc. or it may be larger. All typable words should produce the same output. All non-typable words should also produce the same output.

P.S. Just out of curiosity, is 'tasteless' the longest dictionary word that is typable?
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