To decrease or become reduced (in amount or degree); often used in formal/written contexts.
ここ数年で出生率は徐々に減じている。
The birth rate has gradually been decreasing over the past few years.
薬の投与で患者の痛みはかなり減じた。
With medication, the patient's pain was significantly reduced.
予算の都合で計画の規模が減じられた。
The scale of the plan was reduced because of the budget.
To reduce, lessen, or mitigate something (damage, amount, risk, etc.) — a transitive use indicating intentional reduction.
政府は赤字を減じるために歳出を見直した。
The government reviewed expenditures to reduce the deficit.
リスクを減じる対策を早急に講じる必要がある。
It is necessary to take measures quickly to reduce the risk.
温室効果ガスの排出を減じる努力が求められている。
Efforts are required to reduce greenhouse gas emissions.
To subtract or deduct (an amount) — used in calculations or accounting contexts.
給料から税金を減じた額が手取りとなる。
The take-home pay is the amount after deducting taxes from the salary.
利息を減じて返済総額を計算した。
I calculated the total repayment after subtracting the interest.