i-adjective
Describes a physical sensation of being ticklish, or a situation that makes one feel ticklish.
脇の下がくすぐったい。
My armpits are ticklish.
くすぐったくて笑ってしまった。
It was so ticklish that I laughed.
i-adjective
Used when one feels embarrassed or awkward, often due to excessive praise or attention. Similar to 'it tickles me' in English.
そんなに褒められると、くすぐったいです。
I feel embarrassed when you praise me that much.