hat tier are you in? Since the prime minister announced that regions and cities would be placed in different “tiers” of Covid-19 restrictions, everyone is completely clear about what they aren’t allowed to do, and those carping about the tiers of a clown should stop being so unpatriotic. But why “tiers”? Deriving from the old French tire, a rank or sequence, from tirer (to draw or pull), the noun “tier” is adopted in 16th-century English to mean one among several rows of things stacked atop one another: tiers of oars in ancient galleys, tiers of wine casks and so forth. Pretty soon it also acquired a social sense of rank, which persists when people worry that inequalities in healthcare, say, might lead to a “two-tier system”. That implication could be thought unfortunate for fighting a pandemic, but presumably “tiers” was chosen because “levels” was already taken for the five-colour Covid-19 alert level. If we need another hastily bodged system it will have to come in “tranches”, like the debt packages that caused the financial crash. At least we may take comfort in the fact that eventually all these moments will be lost in time, like tiers in rain. • Steven Poole’s A Word for Every Day of the Year is published by Quercus.