1The more literary equivalent of 通じる — describes a road or route leading through to somewhere, or feelings/ideas being conveyed between people. More common in writing than in casual speech.
この山道は険しいが、隣町まで通ずる。
This mountain path is rough, but it leads through to the neighboring town.
彼の研究は実務に通ずるところが多い。
Much of his research is applicable to practical work.
短い言葉でも気持ちが通ずることがある。
Sometimes feelings are conveyed even with just a few words.
2To flow or pass through a channel — liquid, air, electric current, etc.
雨水はこの溝を通ずるように設計されている。
This is designed so that rainwater flows through this gutter.
電流はこの配線を通ずる。
The current passes through this wiring.
3For words, an explanation, etc. to be understood or comprehended by the other party.
教師の説明が、やっと学生たちに通ずるようになった。
The teacher's explanation finally began to get through to the students.
長い議論の末、彼の本意が相手に通ずることができた。
After a long discussion, his true intent finally got through to the other party.
比喩を使うと、言いたいことがすんなり通ずることが多い。
Using a metaphor often makes what you're trying to say get through more easily.
4(Somewhat literary) For a deed or quality to be connected with or reflect something honorable or admirable.
その行為は、人としての徳に通ずると言える。
That deed could be said to reflect virtue as a human being.
古い作法をわきまえていることは、教養に通ずるところがある。
Knowing old-fashioned etiquette is, in a way, connected with being cultured.
5To be well versed in or knowledgeable about a particular field — used in the pattern 〜に通ずる.
彼は古典文学に通ずる人物だ。
He is a person well versed in classical literature.
この分野に通ずる専門家に相談した方がいい。
You should consult an expert who is well versed in this field.
6(Negative nuance) To secretly communicate or collude with someone, especially an enemy — to be in league with.
彼はスパイと通ずる疑いを持たれている。
He is suspected of secretly colluding with a spy.
裏で敵と通ずる行為は、決して許されない。
Secretly colluding with the enemy is never forgiven.
7To form a close, sympathetic bond with someone — most often used in the set phrase 通ずるところがある ("to have things in common with").
彼とは趣味が合い、通ずるところが多い。
He and I share similar tastes; we have a lot in common.
年齢は違っても、若者の感性に通ずる部分がある。
Even though our ages differ, there are aspects that resonate with youthful sensibilities.