noun
nearby; close by; in the vicinity
Refers to a location that is near the speaker or a reference point. Often used with verbs of existence or movement.
側近くにコンビニがあります。
There is a convenience store nearby.
彼はいつも側近くにいる。
He is always close by.
近く is a more general and common word for 'nearby' or 'soon'. 側近く emphasizes physical proximity to a person or specific location, often with a nuance of being at hand.
そば means 'near' or 'beside' and is used similarly, but 側近く is a compound noun that can stand alone as a location, whereas そば is often used with particles like に or の.
Compound of 側 (そば, 'near') and 近く (ちかく, 'near'), literally 'near-near'. The exact historical derivation is uncertain, but it functions as a noun meaning 'nearby place'.