N4
らしい ①
Seems like, Apparently, I heard
カシキさんの彼氏はカッコいいらしいよ。
I heard that Kashiki-san's boyfriend is handsome.
Explanation
「らしい」 means 'I hear that …' or 'it seems …': a conclusion drawn from what you were told, from the news, or from outside signs, without the speaker taking full responsibility.
「天気予報によると、明日は雨らしい」 (According to the forecast, it seems it will rain tomorrow).
There is usually an outside source of information.
Mixed up with
「そうだ」 (hearsay) passes on what you heard as it is. 「らしい」 means you took that information and reasoned 'so it seems'.
「ようだ」 relies more on what you sensed yourself; 「らしい」 relies on indirect information, and the speaker stays more detached.
After a noun, 「らしい」 takes no 「だ」: 「雨らしい」. The hearsay 「そうだ」 needs it: 「雨だそうだ」.
Note: the 「らしい」 meaning 'typical of' (男らしい) is a different use.