Keyword
measuring ruler
Info
FrequencyTop 2400-2500
Type
Kyōiku (6th grade) 
?
KankenLevel 5
Heisig1151
Readings
さし
(4%)
せき
(1%)
Mnemonic

It's an R for measuring ruler, a tool used to measure short distances.

Used in kanji (8 in total)
translation
midday
completely exhaust
mountain stream
Used in vocabulary (96 in total)
shaku (unit of distance approximately equal to 30.3 cm); rule; measure; length
gauge; standard; length; size; (measuring) rule; scale
approx. 30 cm
Examples (4 in total)
The calorie is an exact measure of the energy in food.
Man is the measure of all things.
Money is the measure of worth.