师长
shīzhǎng · HSK 7
teacher
👨🏫 师 (teacher) + 长 (senior/elder) = a senior teacher, an honored mentor
师 means teacher or master; 长 means elder, chief, or senior. Together 师长 names a respected senior teacher or mentor. The same compound also denotes a military division commander, the senior chief of a unit.
长 — pictograph of long-haired person with cane
Originally a pictograph showing a person with long, flowing hair leaning on a cane, representing an elder. The meaning extended from 'long hair' to 'long' in general, and also to 'elder' or 'to grow' (read zhǎng). The modern form 长 is a simplification of the traditional 長.