overestimate
verb /ˌəʊvərˈestɪmeɪt/
  /ˌəʊvərˈestɪmeɪt/
Verb Forms
| present simple I / you / we / they overestimate |    /ˌəʊvərˈestɪmeɪt/   /ˌəʊvərˈestɪmeɪt/  | 
| he / she / it overestimates |    /ˌəʊvərˈestɪmeɪts/   /ˌəʊvərˈestɪmeɪts/  | 
| past simple overestimated |    /ˌəʊvərˈestɪmeɪtɪd/   /ˌəʊvərˈestɪmeɪtɪd/  | 
| past participle overestimated |    /ˌəʊvərˈestɪmeɪtɪd/   /ˌəʊvərˈestɪmeɪtɪd/  | 
| -ing form overestimating |    /ˌəʊvərˈestɪmeɪtɪŋ/   /ˌəʊvərˈestɪmeɪtɪŋ/  | 
- overestimate something to estimate something to be larger, better, more important, etc. than it really is
- They overestimated his ability when they promoted him.
 - The importance of these findings cannot be overestimated (= is very great).
 
Extra Examples- The Ministry of Finance consistently overestimated its budget deficits.
 - We overestimated the cost by about 2 per cent.
 
Oxford Collocations Dictionaryadverb- considerably
 - greatly
 - grossly
 - …
 
- tend to
 - be easy to
 - be difficult to
 - …
 
- by
 
- something cannot be overestimated