Short for 液体窒素 (ekitai chisso, “liquid nitrogen”).

The katakana syllable チ (chi). Its equivalent in hiragana is ち (chi). It is the seventeenth syllable in the gojūon order; its position is タ行イ段 (ta-gyō i-dan, “row ta, section i”).

childish, immature, young, juvenile, naive