訓 ゆび,さ(す),-さ(し) ・ 音 シ
Sino-Vietnamese: chỉ
Hand 扌 gives the meaning and 旨 (chi) gives the sound: the part of the hand you point with is the finger (Han Viet chi, as in chi dinh = designate).
Stroke data: KanjiVG (CC BY-SA 3.0) — kanjivg.tagaini.net
先生は地図を指して説明しました。 (せんせいはちずをさしてせつめいしました)
The teacher explained while pointing at the map.