矩
jǔ
carpenter's square
rule; regulation; pattern; to carve
arrow/straight tool (矢) + sound (巨) = carpenter's square and rule
矢 originally meant arrow, but here it represents a straight, precise instrument — the kind of rigid tool used to measure and mark right angles. 巨 mainly contributes the sound jǔ and does not add semantic weight.
做事要守规矩，不能随便乱来。
zuò shì yào shǒu guī jǔ，bù néng suí biàn luàn lái。
When doing things you must follow the rules and not just act however you like.
老师说，没有规矩就不成方圆。
lǎo shī shuō，méi yǒu guī jǔ jiù bù chéng fāng yuán。
The teacher said that without rules and standards, nothing can be properly shaped.
Words with 矩
不以规矩，不能成方圆
bù yǐ guī ju , bù néng chéng fāng yuán
without rules, nothing can be done (idiom, from Mencius); one must follow some rules
中心矩
zhōng xīn jǔ
(statistics) central moment
中规中矩
zhòng guī zhòng jǔ
conforming with the norms of society
伴矩阵
bàn jǔ zhèn
adjoint matrix (math.)
偏心矩
piān xīn jǔ
axis of eccentricity
力矩
lì jǔ
torque
原点矩
yuán diǎn jǔ
(statistics) moment
守规矩
shǒu guī ju
to behave oneself; to abide by the rules
循规蹈矩
xún guī dǎo jǔ
to follow the compass and go with the set square (idiom); to follow the rules inflexibly
扭矩
niǔ jǔ
torque
没有规矩，不成方圆
méi yǒu guī ju , bù chéng fāng yuán
without rules, nothing can be done (idiom); one must follow some rules
没有规矩，何以成方圆
méi yǒu guī ju , hé yǐ chéng fāng yuán
without rules, how can anything be done (idiom); one must follow some rules