否
ヒ, いな, いや
negate, no, noes, refuse, decline, deny
JLPT3 G6 S7 F561
As per 不# (refusal; negation) + 口 mouth → oral *refusal/negation/denial* → *no*; *bad*; *otherwise*; *whether or not* → *as soon as*; *no sooner than* (← practically no time between the occurrence of two events). In derivative characters such as 痞 and 嚭, 否 conveys the concept "bulge," a carryover influence of 不.
[Full Kanji Etymology List]