【Load】 ,  【burden】 ,  【freight】 ,  【cargo】 ,  【lading】  are comparable when they mean something which is carried, conveyed, or transported from one place to another.

【Load】 is the most comprehensive of these terms, being applicable to whatever is carried (as by a man, animal, vehicle, ship, running water, or conducting wire). 【Load】 is also applicable to the quantity or amount carried (as by a wagon, a truck, or a 【freight】 car).

【Burden】  may take the place of  【load】 , but in both primary and extended use it ordinarily takes on some of the notions of the cognate verb (see  【BURDEN】  ) and suggests a 【load】 that weighs one down (as from heaviness, unpleasantness, or unwieldiness).

【Freight】 applies to goods or merchandise in transit, especially long-distance transit (as by ship, railway train, or motor truck).

【Cargo】 applies specifically to 【freight】 carried by a ship or aircraft.

【Lading】  is chiefly a poetic or commercial synonym for  【freight】  or  【cargo】 . Are Comparable When They Denote The Means, Especially The Amount Of Money Or Goods, Required To Keep One Supplied With The Necessities Of Life (As Food, Housing, And Clothing) And Sometimes Also The Nonessentials That With The Necessities Supply The Needs Of A Full Life.