threshold

Separated  by a gate 

Components

Meaning component
mén, men door
Meaning component
huò or

Character Evolution

Seal form
Seal Shuowen ~100 AD
Seal form
Seal Shuowen ~100 AD
Clerical form
Clerical Eastern Han 25-220 AD
Regular Modern

Historical Pronunciations

Old Chinese
Zhengzhangqʰʷrɯɡ

說文解字

門榍也。从門或聲。《論語》曰:“行不履閾。”

Sources

Readings & variants
Unicode
Historical pronunciations
Zhengzhang Shangfang
Historical images
Academia Sinica

threshold Simplified

Separated  by a gate 

Components

Meaning component
mén, men door
Meaning component
huò or

Sources

Readings & variants
Unicode