covering

Etymology 1

Present participle or participial adjective from cover (verb) + -ing; or, from Middle English participle form of coveren, keveren (“to cover”).

verb

1. present participle and gerund of cover

Etymology 2

From Middle English coverynge, -inge, keverynge, -inge [verbal noun of coveren, keveren (“to cover”)]; or, verbal noun from cover (verb) + -ing.

noun

1. (countable) That which covers or conceals; a cover">cover; something spread or laid over or wrapped about another.
   Face covering is also mentioned: "There are some circumstances when wearing a face covering may be marginally beneficial as a precautionary measure. The evidence suggests that wearing a face covering does not protect you, but it may protect others if you are infected but have not yet developed symptoms. … If you can, wear a face covering if you need to use public transport." May 20 2020, Richard Clinnick, “Network News: More trains... but advice is not to use public transport”, in Rail, page 6
2. (uncountable) Action of the verb to cover.
3. (topology) A continuous map onto a topological space X, π:E→X, such that there exists a discrete space D and for every x∈X an open neighborhood U⊂X, such that π⁻¹(U)= displaystyle ⨆_(d∈D)V_d and π|_(V_d):V_d→U is a homeomorphism for every d∈D.