This might be coincidental but a lot of words that start with "sn-" are related to either noses or slow, quiet movement, and a lot of words that start with "fl-" are related to bendy/rubbery things, or to rotating or throwing things
"Snail" and "snake" may both be from a proto-Indo-European root *sneg meaning "to crawl" and i think that's a great word for it
Thinking about it more, there's also quite a few "fl-" words related to light or brightness
