This is the 858th most frequent Japanese word.
良かっ
"良かっ" is the past tense stem of "良い" (good), meaning "was good" or "was fine."
Here, '良かった' expresses positive feelings or satisfaction about a completed encounter or experience.
あなたに会えて良かったです。
It was nice meeting you.
In this sentence, '良かった' is used to express relief or approval of a past decision or event.
その映画を見なくて本当に良かった。
It was truly good that I didn't watch that movie.
The word '良かった' here is used as the past tense of '良い' to describe something favorable or pleasing from the past.