Where does this definition of front focal length come from?
This entry for front focal length is sourced from GetWord Corpus, one of the dictionaries and corpora merged into Lughet.
Does front focal length appear elsewhere on Lughet?
Yes — front focal length 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.