Other forms: erected, erecting, erects
To erect something is to build it upright, or to put it up. A tent, a fence, a statue in a square.
The verb is formal and belongs to planning notices and histories: permission to erect a building, a monument erected in 1920. In ordinary speech you put a tent up rather than erect one. There is also an adjective, and erect means standing straight — sitting erect, an erect posture, ears erect. Both share the idea of upright, and because the noun erection covers the anatomical sense as well, careful writing often prefers construction.
1verberectTo build or put up something upright.
“They erected a marquee on the lawn.”
2adjectivestraightUpright and straight.
“She sat erect in the hard chair.”
Too few real examples of this word to estimate which sense is commonest.
Erect is straightened out. Latin ērigō joins ē, out, to regō, to keep straight or to guide, and it is the same regō that lies behind direct.
Proto-Indo-European
*h₃reǵ-
Latin
ērectus — upright
Middle English
erect
English, today
erect
Built from
From Middle English erect, a borrowing from Latin ērectus (“upright”), past participle of ērigō (“raise, set up”), from ē- (“out”) + regō (“to direct, keep straight, guide”).
Etymology from Wiktionary, CC BY-SA