miscellaneous thoughts; random impressions
Used for a collection of casual, unsystematic thoughts or impressions on a topic, often in titles of essays, columns, or blog posts.
彼のブログには旅先での雑感が綴られている。
His blog is filled with miscellaneous thoughts from his travels.
会議の後、参加者から雑感を聞いた。
After the meeting, I asked the participants for their random impressions.
Compound of 雑 (ざつ, miscellaneous) and 感 (かん, feeling/impression). The reading ざっかん results from assimilation of つ to っ before a k-row sound.