すぐ

• (Tokyo) すぐ [súꜜgù] (Atamadaka – [1])^[1]
• IPA^(key): [sɨɡɯ̟]

From Old Japanese, from Proto-Japonic *sunku. Cognate with Northern Amami Ōshima 直ぐ (sïgu), Okinawan 直ぐ (sigu), Miyako 直ぐ (sugu), Yaeyama 直ぐ (sïgu), Yonaguni 直く゚ (chi'ngu).

Likely derived from root verb form sugu. The expected adjectival or adverbial form would be sugi, but there is evidence for sugu used in this way in ancient eastern dialects.^[2]

Notably, the modern verbs 過ぎる (sugiru) and 挿げる (sugeru) derived from sugu (see further below) have shared underlying senses of “going through; directly; without stopping or turning”, indicative of this common root.

• 直ぐ, 直

すぐ • (sugu) -na (adnominal すぐな (sugu na), adverbial すぐに (sugu ni))

1. straight, not bent

すぐ • (sugu) 

1. 直ぐ: immediately, right away, soon

   すぐ行(い)くよ

   sugu iku yo

   I'll be there right away.

2. 直ぐ: quick to

   すぐ怒(おこ)る

   sugu okoru

   quick to anger

3. 直ぐ: right next to, right close by

   すぐ上(うえ)に

   sugu ue ni

   right on top

   コンビニはすぐそこだよ。

   Konbini wa sugu soko da yo.

   The convenience store is right over there.

• (soon): そろそろ (sorosoro), 直(じき) (jiki), 直(じか) (jika), 直(ただ)ち (tadachi)

• すぐに (sugu ni): immediately; directly
• すぐと (sugu to): immediately; directly
• 真(ま)っ直(す)ぐ (massugu): straight; straightforward, honest

• 今(いま) (ima): now

The reading of various kanji terms.

すぐ • (sugu) ^†nidan

1. (obsolete) 過ぐ: classical form of modern 過ぎる (sugiru, “to go through, to go past; to exceed”)

すぐ • (sugu) ^†nidan

1. (obsolete) 挿ぐ: classical form of modern 挿げる (sugeru, “to connect or affix one thing to another, especially by passing something through something else”)

すぐ (sugu) 

1. 直ぐ: immediately