Where does “häveliäinen” come from?

häveliäinen (Finnish) comes from Finnish häveliäs, from Finnish häpy, from Finnish -u, from Proto-Finnic -u — Forms nouns from adjectives, nouns.

Ancestry of “häveliäinen”, step by step

Step	Language	Word	Meaning
1	Finnish	häveliäs	Modest, bashful
2	Finnish	häpy	vulva; genitalia; shame
3	Finnish	-u	Forms nouns from verbs. Most common with "e"- and...
4	Proto-Finnic	-u	Forms nouns from adjectives, nouns