Several parts combine into one character.

少 builds directly on 小 (small): take 小 and shave one more diagonal stroke off — "smaller still / fewer / less / younger". The character preserves the original 小 inside it, with the extra ノ stroke representing the act of subtraction. Identical across 繁體 / 新字体 / 简体.

Mandarin has TWO tones for 少 — another 破音字: — shǎo (3rd tone): few / less / lacking. 多少 (duōshao, how much), 缺少 (quēshǎo, lack), 很少 (hěnshǎo, very few / rarely), 减少 (jiǎnshǎo, decrease). — shào (4th tone): young / youth (the second meaning of 少 — "having lived few years"). 少年 (shàonián, young man), 少女 (shàonǚ, young woman), 老少 (lǎoshào, old and young), 青少年 (qīngshàonián, teenager). The tone change tracks the meaning shift exactly: shǎo = "few", shào = "young".

Japanese: on-reading ショウ (shō) — 少数 (shōsū, few in number / minority), 少年 (shōnen, young boy — Shōnen Jump 少年ジャンプ is one of the most famous manga magazines), 少女 (shōjo, young girl — and a manga genre name), 減少 (genshō, decrease), 多少 (tashō, somewhat / a little), 少々 (shōshō, "a little / just a moment" — polite request softener). Kun-readings: すく.ない (suku.nai, few / not many) — 少ない (sukunai, few), すこ.し (suko.shi, a little). The polite Japanese word for "wait a moment" is しょうしょう お待ちください (shōshō omachi kudasai) — using on-reading 少々.

少 / 多 form one of the fundamental quantity oppositions in CJK languages, parallel to 大 / 小 for size.

Memory aid: 小 with one stroke shaved off — even smaller, even fewer.