Where does this definition of thumb index come from?
This entry for thumb index is sourced from Main Dictionary, one of the dictionaries and corpora merged into Lughet.
Is thumb index a noun, verb, or something else?
In this entry, thumb index is tagged as noun.
Does thumb index appear elsewhere on Lughet?
Yes — thumb index appears under other sources or language pairs in Lughet's collection. See the list below.
What is Lughet?
Lughet is a free trilingual dictionary covering nearly five million entries across Uyghur, Chinese, and English, drawn from more than ten source dictionaries and corpora.