Today’s #kanji is 幾, which is listed under the radical of #いとがしら（幺） and it is a compound ideograph made of 幺x2 meaning “very small” and 戍 meaning “soldiers defending.” In order for soldiers to defend, they need to know the minute movements of the enemy, so 幾 has developed the meaning of “an omen” my dictionary says.

Meaning: an omen, unknown number/quantity (how many, how much)
Reading: キ、いく

幾何学（キカガク）: geometry
幾微（キビ）: niceties, fine points, subtleties (usually written 機微 with the same sound)

幾（いく）つ: (question) how many, how old (usually written in Hiragana)
幾（いく）ら: (question) how much (usually written in Hiragana)
幾多（いくた）の: many, numerous
幾年（いくとせ/いくネン）: n. (question) how many years, (infinite) some years
幾分（いくブン）: a part, a portion; to some extent, somewhat