Help with monomorphic, polyphonic verbs

Question

OK, I kind of invented that term. But I'm referring to verbs that have identical kanji and okurigana; have nearly identical meanings; but have different readings. I'm sure there are many others out there, but some that immediately come to mind are:

• [解]{と}く・[解]{ほど}く
• [抱]{だ}く・[抱]{いだ}く
• [溶]{と}ける・[溶]{とろ}ける
  • Although I believe the latter is more often written as 蕩ける
• [埋]{う}める・[埋]{うず}める
• [脅]{おど}かす・[脅]{おびや}かす

The typical answer is that context dictates the usage. However, when the meanings are so close, or even overlap, context doesn't (really) help. So how do you know which reading to use? Is it dealer's choice at that point?

Admittedly, I have a fairly clear grasp on the nuances between [抱]{だ}く and [抱]{いだ}く, since [抱]{いだ}く usually has a more figurative meaning. But even looking it up now, I see that [抱]{いだ}く can also mean "to physically hold in one's arms" (which I didn't previously know). But at least we know a nuance exists.

However, I often see 脅かす show up in my Japanese Bible. And maybe it's just me, but I don't see any nuance differentiating the two. So I never know how it's supposed to be read.

So what's the non-native reader to do? Is it just a matter of learning the subtleties and memorizing them? Do nuances even necessarily exist in all cases?

Answer 1

Although you may hate this, after all 'context' is the only clue. Generally there are cases where ambiguity remains. That said, really ambiguous cases are not so frequent and 脅かす（おどかす・おびやかす) is one of the rare cases.

The following is an example for おびやかす

• 刃物で人を脅かす

But I think most native speakers would read it as おどかす. This is a case where only the writer knows how to read it. Still in most cases おどかす/おびやかす are distinct. For example,

• [脅]{おど}かさないで Don't scare me
• 平和を[脅]{おびや}かす Subj. threatens peace or Peace-threatening

As you are probably aware, the objects of おどかす/おびやかす are (usually) different (roughly animate vs. inanimate), but they can overlap and reading will be ambiguous in such cases . (Cf. here)

(In the above example "刃物で人を脅かす", おどかす/おびやかす mean mostly the same; おびやかす sounds actually a bit weird to me.)

---

Practically the following may be useful.

Use of hiragana

As for the examples mentioned in the question, the second reading is less frequent and simply hiragana will be used. This is true especially of ほどく and とろける. So 解く and 溶ける are likely to be read as とく/とける. 脅かす is a borderline case, I guess.

Collocations/Fixed Expressions

Like 平和を脅かす, the second reading is more common in some fixed combination of words. E.g. 大志を[抱]{いだ}く, 骨を[埋]{うず}める、手紙を[認]{したた}める. Except for this kind of expressions, these kanjis tend to be read in the first reading (だく,うめる,みとめる).

Contexts

There are cases where contexts usually disambiguate: この道を通った can be read とおった or かよった, depending on whether you just passed the road once or used the road to commute to somewhere.

臭い(におい、くさい) is another word usually disambiguated by contexts or probably by grammar.

---

This page lists the kind of words you mention in the question.

Answer 2

If it's any help, corpora seem to treat 脅かす（おびやかす）as emphasizing the meaning of abstract threats. For example, NINJAL list phrases like 命を脅かす and 安全が脅かされる (among others) as the making up the bulk of the entries. This might suggest that おびやかす has the nuance of something abstract being threatened (life, safety, wellbeing, economy, etc.). In contrast, the same corpus lists 脅す as often relating to threats to named individuals, like 里見を拳銃で脅して. I know you wanted to specifically compare the two variants obiyakasu and odokasu, but there may not be a lot of data on which to form a solid conclusion.

The typical answer of context mattering isn't just some linguistic platitude - it is based on experience, research, and corpus linguistics. Collocations undoubtedly play a role too, but without doing a detailed corpus analysis of specific words in specific linguistic environments, I'm afraid you might not be satisfied with what is likely to be a variety of somewhat general answers. You could consider Content Analysis, but again that is a rather tedious undertaking for a very specific niche word.

Links: (might require registration)
https://nlb.ninjal.ac.jp/headword/V.01390/
https://nlb.ninjal.ac.jp/headword/V.01506/