This is the 878th most frequent Finnish word.
miestä
"Miestä" is the partitive singular form of "mies," meaning "man" in English.
In this sentence, 'miestä' (the partitive form of 'mies') is used as the object of the verb 'näin'.
Näin eilen miestä torilla.
I saw a man at the marketplace yesterday.
Here, 'miestä' (partitive form) is used because the action of 'auttaa' (helps) takes its object in partitive case in Finnish.
Hän auttaa miestä, joka tarvitsee apua.
He/She is helping a man who needs help.
'Miestä varten' is an adpositional expression where 'miestä' is in the partitive case, expressing 'for the man'.