Acid-catalysed hydrolysis of ethyl acetate, $\mathrm{CH_3COOC_2H_5 + H_2O \to CH_3COOH + C_2H_5OH}$, follows pseudo first-order kinetics. The pseudo first-order behaviour arises because:

The true rate law is $\text{Rate} = k[\mathrm{ester}][\mathrm{H_2O}]$, second order overall. Because water is the solvent and present in huge excess, $[\mathrm{H_2O}]$ stays essentially unchanged through the reaction and is absorbed into a new constant $k' = k[\mathrm{H_2O}]$. The observed rate then reduces to $\text{Rate} = k'[\mathrm{ester}]$, which is first order in form, hence the name pseudo first-order.