Eastern Standard Time. Also,E.S.T.,e.s.t.
a suffix forming the superlative degree of adjectives and adverbs: warmest; fastest; soonest.
a native English suffix formerly used to form the second person singular indicative of verbs: knowest; sayest; goest. Also,-st.
Random House Unabridged Dictionary, Copyright © 1997, by Random House, Inc., on Infoplease.