Why do JLPT N1 learners confuse 遅くとも with 彼此?

Both words occupy adjacent semantic territory, which is exactly why the JLPT uses them as distractors for each other on multiple-choice items. The fastest way to stop confusing them is to study them as a pair, write a one-sentence contrast in your own words, and drill the pair specifically rather than each word in isolation.

Is 遅くとも or 彼此 more common on JLPT N1?

Both appear in the JLPT N1 curriculum and either may show up on a given exam. Don't try to predict which one the test will choose — learn to distinguish them and you'll be safe regardless. Both belong to the General Expressions (2) theme of N1 vocabulary.

How do I practice this confusion pair?

Free option: visit /try and pick a confusion drill. Paid option: none — JLPT Mastery is free during launch. Whichever route you take, the engine specifically re-tests pairs you've gotten wrong rather than rotating through general vocabulary review.

JLPT N1 · Advanced · Meaning confusion

遅くとも vs 彼此

Q: What's the difference between 遅くとも and 彼此?

遅くとも (おそくとも) means "at the latest" and 彼此 (あれこれ) means "one thing or another; this and that; this or that". Both are complex adverbial phrases. 'Osokutomo' (遅くとも) specifies a time constraint, while 'arekore' (彼此) lists multiple options or things. Learners may confuse them when describing final choices or deadlines in a sequence.

Why JLPT N1 learners mix up 遅くとも (おそくとも, “at the latest”) and 彼此 (あれこれ, “one thing or another; this and that; this or that”).

遅くとも

おそくとも

at the latest

adverb

彼此

あれこれ

one thing or another; this and that; this or that

adverb

Theme: General Expressions (2)JLPT N1

Why these get confused

Both are complex adverbial phrases. 'Osokutomo' (遅くとも) specifies a time constraint, while 'arekore' (彼此) lists multiple options or things. Learners may confuse them when describing final choices or deadlines in a sequence.

How to tell them apart

Anchor on the meaning, not the form. 遅くとも (at the latest) and 彼此 (one thing or another; this and that; this or that) live in adjacent semantic territory. Memorize the boundary, not just each word.
Read the example sentences below. Seeing each word in its natural context builds a faster lookup than studying the dictionary form alone.

In a sentence

遅くとも (at the latest)

遅くとも6時には来い。
遅くともやらないよりはまし。

彼此 (one thing or another; this and that; this or that)

私にあれこれ指図するのは、やめてください。
あれこれ指図するのは止めろ。

How JLPT tests this pair

On JLPT N1, this pair shows up as a vocabulary meaning question. You see one word and pick its English equivalent from four options — one of which will be the other word in this pair, chosen as a distractor precisely because of the overlap.

Sample item

「遅くとも」の意味は？