one advantage; a single merit
Used when pointing out a single positive aspect, often in contrast to drawbacks. Commonly appears in set phrases like 一利一害 (one advantage and one disadvantage).
This plan has not a single advantage.
何事にも一利一害がある。
Everything has its pros and cons.
advantages and disadvantages; gain some, lose some
Compound of 一 (one) and 利 (advantage, profit). The reading いちり is the standard on'yomi combination.