Word: unfast
Part of speech: Adjective
Syllables: un
fast
Definition: Not fast or safe; not secure.
Morphemes:
Affix: un-
Language: en
PoS: Prefix
Meaning: absent; lacking; not; negative
Affix: fast
Language: en
PoS: Adjective
Meaning: Steadfast, with unwavering feeling. (Now mostly in set phrases like fast friend(s) .)